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[PATCH 2/3] Add operator <->(box, point) to GiST box_ops 128+ messages / 11 participants [nested] [flat]
* [PATCH 2/3] Add operator <->(box, point) to GiST box_ops @ 2019-03-07 20:49 Nikita Glukhov <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Nikita Glukhov @ 2019-03-07 20:49 UTC (permalink / raw) --- doc/src/sgml/gist.sgml | 1 + src/backend/access/gist/gistproc.c | 49 +++++++++++++++--------- src/include/catalog/pg_amop.dat | 3 ++ src/include/catalog/pg_amproc.dat | 2 + src/include/catalog/pg_proc.dat | 4 ++ src/test/regress/expected/gist.out | 76 ++++++++++++++++++++++++++++++++++++++ src/test/regress/sql/gist.sql | 16 ++++++++ 7 files changed, 134 insertions(+), 17 deletions(-) diff --git a/doc/src/sgml/gist.sgml b/doc/src/sgml/gist.sgml index 763b8cf..2b43dfc 100644 --- a/doc/src/sgml/gist.sgml +++ b/doc/src/sgml/gist.sgml @@ -83,6 +83,7 @@ <literal>~=</literal> </entry> <entry> + <literal><-></literal> </entry> </row> <row> diff --git a/src/backend/access/gist/gistproc.c b/src/backend/access/gist/gistproc.c index 1826b51..a668283 100644 --- a/src/backend/access/gist/gistproc.c +++ b/src/backend/access/gist/gistproc.c @@ -1464,26 +1464,13 @@ gist_point_distance(PG_FUNCTION_ARGS) PG_RETURN_FLOAT8(distance); } -/* - * The inexact GiST distance method for geometric types that store bounding - * boxes. - * - * Compute lossy distance from point to index entries. The result is inexact - * because index entries are bounding boxes, not the exact shapes of the - * indexed geometric types. We use distance from point to MBR of index entry. - * This is a lower bound estimate of distance from point to indexed geometric - * type. - */ static float8 -gist_bbox_distance(GISTENTRY *entry, Datum query, - StrategyNumber strategy, bool *recheck) +gist_box_distance_helper(GISTENTRY *entry, Datum query, + StrategyNumber strategy) { float8 distance; StrategyNumber strategyGroup = strategy / GeoStrategyNumberOffset; - /* Bounding box distance is always inexact. */ - *recheck = true; - switch (strategyGroup) { case PointStrategyNumberGroup: @@ -1500,6 +1487,32 @@ gist_bbox_distance(GISTENTRY *entry, Datum query, } Datum +gist_box_distance(PG_FUNCTION_ARGS) +{ + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); + Datum query = PG_GETARG_DATUM(1); + StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2); + + /* Oid subtype = PG_GETARG_OID(3); */ + /* bool *recheck = (bool *) PG_GETARG_POINTER(4); */ + float8 distance; + + distance = gist_box_distance_helper(entry, query, strategy); + + PG_RETURN_FLOAT8(distance); +} + +/* + * The inexact GiST distance methods for geometric types that store bounding + * boxes. + * + * Compute lossy distance from point to index entries. The result is inexact + * because index entries are bounding boxes, not the exact shapes of the + * indexed geometric types. We use distance from point to MBR of index entry. + * This is a lower bound estimate of distance from point to indexed geometric + * type. + */ +Datum gist_circle_distance(PG_FUNCTION_ARGS) { GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); @@ -1510,7 +1523,8 @@ gist_circle_distance(PG_FUNCTION_ARGS) bool *recheck = (bool *) PG_GETARG_POINTER(4); float8 distance; - distance = gist_bbox_distance(entry, query, strategy, recheck); + distance = gist_box_distance_helper(entry, query, strategy); + *recheck = true; PG_RETURN_FLOAT8(distance); } @@ -1526,7 +1540,8 @@ gist_poly_distance(PG_FUNCTION_ARGS) bool *recheck = (bool *) PG_GETARG_POINTER(4); float8 distance; - distance = gist_bbox_distance(entry, query, strategy, recheck); + distance = gist_box_distance_helper(entry, query, strategy); + *recheck = true; PG_RETURN_FLOAT8(distance); } diff --git a/src/include/catalog/pg_amop.dat b/src/include/catalog/pg_amop.dat index cf63eb7..ebc38ae 100644 --- a/src/include/catalog/pg_amop.dat +++ b/src/include/catalog/pg_amop.dat @@ -1081,6 +1081,9 @@ amopstrategy => '13', amopopr => '~(box,box)', amopmethod => 'gist' }, { amopfamily => 'gist/box_ops', amoplefttype => 'box', amoprighttype => 'box', amopstrategy => '14', amopopr => '@(box,box)', amopmethod => 'gist' }, +{ amopfamily => 'gist/box_ops', amoplefttype => 'box', amoprighttype => 'point', + amopstrategy => '15', amoppurpose => 'o', amopopr => '<->(box,point)', + amopmethod => 'gist', amopsortfamily => 'btree/float_ops' }, # gist point_ops { amopfamily => 'gist/point_ops', amoplefttype => 'point', diff --git a/src/include/catalog/pg_amproc.dat b/src/include/catalog/pg_amproc.dat index 020b741..5567b7e 100644 --- a/src/include/catalog/pg_amproc.dat +++ b/src/include/catalog/pg_amproc.dat @@ -419,6 +419,8 @@ amprocrighttype => 'box', amprocnum => '6', amproc => 'gist_box_picksplit' }, { amprocfamily => 'gist/box_ops', amproclefttype => 'box', amprocrighttype => 'box', amprocnum => '7', amproc => 'gist_box_same' }, +{ amprocfamily => 'gist/box_ops', amproclefttype => 'box', + amprocrighttype => 'box', amprocnum => '8', amproc => 'gist_box_distance' }, { amprocfamily => 'gist/poly_ops', amproclefttype => 'polygon', amprocrighttype => 'polygon', amprocnum => '1', amproc => 'gist_poly_consistent' }, diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index e0852b8..762c099 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -7844,6 +7844,10 @@ { oid => '2584', descr => 'GiST support', proname => 'gist_box_same', prorettype => 'internal', proargtypes => 'box box internal', prosrc => 'gist_box_same' }, +{ oid => '3998', descr => 'GiST support', + proname => 'gist_box_distance', prorettype => 'float8', + proargtypes => 'internal box int2 oid internal', + prosrc => 'gist_box_distance' }, { oid => '2585', descr => 'GiST support', proname => 'gist_poly_consistent', prorettype => 'bool', proargtypes => 'internal polygon int2 oid internal', diff --git a/src/test/regress/expected/gist.out b/src/test/regress/expected/gist.out index 0a43449..2234876 100644 --- a/src/test/regress/expected/gist.out +++ b/src/test/regress/expected/gist.out @@ -203,6 +203,82 @@ select b from gist_tbl where b <@ box(point(5,5), point(6,6)); (6,6),(6,6) (21 rows) +-- Also test an index-only knn-search +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + QUERY PLAN +------------------------------------------------------ + Index Only Scan using gist_tbl_box_index on gist_tbl + Index Cond: (b <@ '(6,6),(5,5)'::box) + Order By: (b <-> '(5.2,5.91)'::point) +(3 rows) + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + b +------------------------- + (5.55,5.55),(5.55,5.55) + (5.6,5.6),(5.6,5.6) + (5.5,5.5),(5.5,5.5) + (5.65,5.65),(5.65,5.65) + (5.45,5.45),(5.45,5.45) + (5.7,5.7),(5.7,5.7) + (5.4,5.4),(5.4,5.4) + (5.75,5.75),(5.75,5.75) + (5.35,5.35),(5.35,5.35) + (5.8,5.8),(5.8,5.8) + (5.3,5.3),(5.3,5.3) + (5.85,5.85),(5.85,5.85) + (5.25,5.25),(5.25,5.25) + (5.9,5.9),(5.9,5.9) + (5.2,5.2),(5.2,5.2) + (5.95,5.95),(5.95,5.95) + (5.15,5.15),(5.15,5.15) + (6,6),(6,6) + (5.1,5.1),(5.1,5.1) + (5.05,5.05),(5.05,5.05) + (5,5),(5,5) +(21 rows) + +-- Check commuted case as well +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + QUERY PLAN +------------------------------------------------------ + Index Only Scan using gist_tbl_box_index on gist_tbl + Index Cond: (b <@ '(6,6),(5,5)'::box) + Order By: (b <-> '(5.2,5.91)'::point) +(3 rows) + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + b +------------------------- + (5.55,5.55),(5.55,5.55) + (5.6,5.6),(5.6,5.6) + (5.5,5.5),(5.5,5.5) + (5.65,5.65),(5.65,5.65) + (5.45,5.45),(5.45,5.45) + (5.7,5.7),(5.7,5.7) + (5.4,5.4),(5.4,5.4) + (5.75,5.75),(5.75,5.75) + (5.35,5.35),(5.35,5.35) + (5.8,5.8),(5.8,5.8) + (5.3,5.3),(5.3,5.3) + (5.85,5.85),(5.85,5.85) + (5.25,5.25),(5.25,5.25) + (5.9,5.9),(5.9,5.9) + (5.2,5.2),(5.2,5.2) + (5.95,5.95),(5.95,5.95) + (5.15,5.15),(5.15,5.15) + (6,6),(6,6) + (5.1,5.1),(5.1,5.1) + (5.05,5.05),(5.05,5.05) + (5,5),(5,5) +(21 rows) + drop index gist_tbl_box_index; -- Test that an index-only scan is not chosen, when the query involves the -- circle column (the circle opclass does not support index-only scans). diff --git a/src/test/regress/sql/gist.sql b/src/test/regress/sql/gist.sql index 657b195..b9d398e 100644 --- a/src/test/regress/sql/gist.sql +++ b/src/test/regress/sql/gist.sql @@ -109,6 +109,22 @@ select b from gist_tbl where b <@ box(point(5,5), point(6,6)); -- execute the same select b from gist_tbl where b <@ box(point(5,5), point(6,6)); +-- Also test an index-only knn-search +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + +-- Check commuted case as well +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + drop index gist_tbl_box_index; -- Test that an index-only scan is not chosen, when the query involves the -- 2.7.4 --------------C466D744B1EAB9FA85D22553 Content-Type: text/x-patch; name="0003-Add-operator-box-point-to-SP-GiST-box_ops-v03.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="0003-Add-operator-box-point-to-SP-GiST-box_ops-v03.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH 2/3] Add operator <->(box, point) to GiST box_ops @ 2019-03-07 20:49 Nikita Glukhov <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Nikita Glukhov @ 2019-03-07 20:49 UTC (permalink / raw) --- doc/src/sgml/gist.sgml | 1 + src/backend/access/gist/gistproc.c | 53 ++++++++++++++++++-------- src/include/catalog/pg_amop.dat | 3 ++ src/include/catalog/pg_amproc.dat | 2 + src/include/catalog/pg_proc.dat | 4 ++ src/test/regress/expected/gist.out | 76 ++++++++++++++++++++++++++++++++++++++ src/test/regress/sql/gist.sql | 16 ++++++++ 7 files changed, 140 insertions(+), 15 deletions(-) diff --git a/doc/src/sgml/gist.sgml b/doc/src/sgml/gist.sgml index 44a3b2c..e903319 100644 --- a/doc/src/sgml/gist.sgml +++ b/doc/src/sgml/gist.sgml @@ -83,6 +83,7 @@ <literal>~=</literal> </entry> <entry> + <literal><-></literal> </entry> </row> <row> diff --git a/src/backend/access/gist/gistproc.c b/src/backend/access/gist/gistproc.c index c9da230..89643b4 100644 --- a/src/backend/access/gist/gistproc.c +++ b/src/backend/access/gist/gistproc.c @@ -1464,26 +1464,13 @@ gist_point_distance(PG_FUNCTION_ARGS) PG_RETURN_FLOAT8(distance); } -/* - * The inexact GiST distance method for geometric types that store bounding - * boxes. - * - * Compute lossy distance from point to index entries. The result is inexact - * because index entries are bounding boxes, not the exact shapes of the - * indexed geometric types. We use distance from point to MBR of index entry. - * This is a lower bound estimate of distance from point to indexed geometric - * type. - */ static float8 -gist_bbox_distance(GISTENTRY *entry, Datum query, - StrategyNumber strategy, bool *recheck) +gist_box_distance_helper(GISTENTRY *entry, Datum query, + StrategyNumber strategy) { float8 distance; StrategyNumber strategyGroup = strategy / GeoStrategyNumberOffset; - /* Bounding box distance is always inexact. */ - *recheck = true; - switch (strategyGroup) { case PointStrategyNumberGroup: @@ -1500,6 +1487,42 @@ gist_bbox_distance(GISTENTRY *entry, Datum query, } Datum +gist_box_distance(PG_FUNCTION_ARGS) +{ + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); + Datum query = PG_GETARG_DATUM(1); + StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2); + + /* Oid subtype = PG_GETARG_OID(3); */ + /* bool *recheck = (bool *) PG_GETARG_POINTER(4); */ + float8 distance; + + distance = gist_box_distance_helper(entry, query, strategy); + + PG_RETURN_FLOAT8(distance); +} + +/* + * The inexact GiST distance method for geometric types that store bounding + * boxes. + * + * Compute lossy distance from point to index entries. The result is inexact + * because index entries are bounding boxes, not the exact shapes of the + * indexed geometric types. We use distance from point to MBR of index entry. + * This is a lower bound estimate of distance from point to indexed geometric + * type. + */ +static float8 +gist_bbox_distance(GISTENTRY *entry, Datum query, + StrategyNumber strategy, bool *recheck) +{ + /* Bounding box distance is always inexact. */ + *recheck = true; + + return gist_box_distance_helper(entry, query, strategy); +} + +Datum gist_circle_distance(PG_FUNCTION_ARGS) { GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); diff --git a/src/include/catalog/pg_amop.dat b/src/include/catalog/pg_amop.dat index 0ab95d8..8e74f86 100644 --- a/src/include/catalog/pg_amop.dat +++ b/src/include/catalog/pg_amop.dat @@ -1081,6 +1081,9 @@ amopstrategy => '13', amopopr => '~(box,box)', amopmethod => 'gist' }, { amopfamily => 'gist/box_ops', amoplefttype => 'box', amoprighttype => 'box', amopstrategy => '14', amopopr => '@(box,box)', amopmethod => 'gist' }, +{ amopfamily => 'gist/box_ops', amoplefttype => 'box', amoprighttype => 'point', + amopstrategy => '15', amoppurpose => 'o', amopopr => '<->(box,point)', + amopmethod => 'gist', amopsortfamily => 'btree/float_ops' }, # gist point_ops { amopfamily => 'gist/point_ops', amoplefttype => 'point', diff --git a/src/include/catalog/pg_amproc.dat b/src/include/catalog/pg_amproc.dat index 020b741..5567b7e 100644 --- a/src/include/catalog/pg_amproc.dat +++ b/src/include/catalog/pg_amproc.dat @@ -419,6 +419,8 @@ amprocrighttype => 'box', amprocnum => '6', amproc => 'gist_box_picksplit' }, { amprocfamily => 'gist/box_ops', amproclefttype => 'box', amprocrighttype => 'box', amprocnum => '7', amproc => 'gist_box_same' }, +{ amprocfamily => 'gist/box_ops', amproclefttype => 'box', + amprocrighttype => 'box', amprocnum => '8', amproc => 'gist_box_distance' }, { amprocfamily => 'gist/poly_ops', amproclefttype => 'polygon', amprocrighttype => 'polygon', amprocnum => '1', amproc => 'gist_poly_consistent' }, diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 3800150..d6477a3 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -7760,6 +7760,10 @@ { oid => '2584', descr => 'GiST support', proname => 'gist_box_same', prorettype => 'internal', proargtypes => 'box box internal', prosrc => 'gist_box_same' }, +{ oid => '3998', descr => 'GiST support', + proname => 'gist_box_distance', prorettype => 'float8', + proargtypes => 'internal box int2 oid internal', + prosrc => 'gist_box_distance' }, { oid => '2585', descr => 'GiST support', proname => 'gist_poly_consistent', prorettype => 'bool', proargtypes => 'internal polygon int2 oid internal', diff --git a/src/test/regress/expected/gist.out b/src/test/regress/expected/gist.out index f5a2993..e8c2685 100644 --- a/src/test/regress/expected/gist.out +++ b/src/test/regress/expected/gist.out @@ -205,6 +205,82 @@ select b from gist_tbl where b <@ box(point(5,5), point(6,6)); (6,6),(6,6) (21 rows) +-- Also test an index-only knn-search +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + QUERY PLAN +------------------------------------------------------ + Index Only Scan using gist_tbl_box_index on gist_tbl + Index Cond: (b <@ '(6,6),(5,5)'::box) + Order By: (b <-> '(5.2,5.91)'::point) +(3 rows) + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + b +------------------------- + (5.55,5.55),(5.55,5.55) + (5.6,5.6),(5.6,5.6) + (5.5,5.5),(5.5,5.5) + (5.65,5.65),(5.65,5.65) + (5.45,5.45),(5.45,5.45) + (5.7,5.7),(5.7,5.7) + (5.4,5.4),(5.4,5.4) + (5.75,5.75),(5.75,5.75) + (5.35,5.35),(5.35,5.35) + (5.8,5.8),(5.8,5.8) + (5.3,5.3),(5.3,5.3) + (5.85,5.85),(5.85,5.85) + (5.25,5.25),(5.25,5.25) + (5.9,5.9),(5.9,5.9) + (5.2,5.2),(5.2,5.2) + (5.95,5.95),(5.95,5.95) + (5.15,5.15),(5.15,5.15) + (6,6),(6,6) + (5.1,5.1),(5.1,5.1) + (5.05,5.05),(5.05,5.05) + (5,5),(5,5) +(21 rows) + +-- Check commuted case as well +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + QUERY PLAN +------------------------------------------------------ + Index Only Scan using gist_tbl_box_index on gist_tbl + Index Cond: (b <@ '(6,6),(5,5)'::box) + Order By: (b <-> '(5.2,5.91)'::point) +(3 rows) + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + b +------------------------- + (5.55,5.55),(5.55,5.55) + (5.6,5.6),(5.6,5.6) + (5.5,5.5),(5.5,5.5) + (5.65,5.65),(5.65,5.65) + (5.45,5.45),(5.45,5.45) + (5.7,5.7),(5.7,5.7) + (5.4,5.4),(5.4,5.4) + (5.75,5.75),(5.75,5.75) + (5.35,5.35),(5.35,5.35) + (5.8,5.8),(5.8,5.8) + (5.3,5.3),(5.3,5.3) + (5.85,5.85),(5.85,5.85) + (5.25,5.25),(5.25,5.25) + (5.9,5.9),(5.9,5.9) + (5.2,5.2),(5.2,5.2) + (5.95,5.95),(5.95,5.95) + (5.15,5.15),(5.15,5.15) + (6,6),(6,6) + (5.1,5.1),(5.1,5.1) + (5.05,5.05),(5.05,5.05) + (5,5),(5,5) +(21 rows) + drop index gist_tbl_box_index; -- Test that an index-only scan is not chosen, when the query involves the -- circle column (the circle opclass does not support index-only scans). diff --git a/src/test/regress/sql/gist.sql b/src/test/regress/sql/gist.sql index bae722f..406fb83 100644 --- a/src/test/regress/sql/gist.sql +++ b/src/test/regress/sql/gist.sql @@ -111,6 +111,22 @@ select b from gist_tbl where b <@ box(point(5,5), point(6,6)); -- execute the same select b from gist_tbl where b <@ box(point(5,5), point(6,6)); +-- Also test an index-only knn-search +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + +-- Check commuted case as well +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + drop index gist_tbl_box_index; -- Test that an index-only scan is not chosen, when the query involves the -- 2.7.4 --------------B01ADF66983FA504E371CA13 Content-Type: text/x-patch; name="0003-Add-box-point-distance-operator-to-SP-GiST-box_ops-v01.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename*0="0003-Add-box-point-distance-operator-to-SP-GiST-box_ops-v01."; filename*1="patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH 2/3] Add operator <->(box, point) to GiST box_ops @ 2019-03-07 20:49 Nikita Glukhov <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Nikita Glukhov @ 2019-03-07 20:49 UTC (permalink / raw) --- doc/src/sgml/gist.sgml | 1 + src/backend/access/gist/gistproc.c | 53 ++++++++++++++++++-------- src/include/catalog/pg_amop.dat | 3 ++ src/include/catalog/pg_amproc.dat | 2 + src/include/catalog/pg_proc.dat | 4 ++ src/test/regress/expected/gist.out | 76 ++++++++++++++++++++++++++++++++++++++ src/test/regress/sql/gist.sql | 16 ++++++++ 7 files changed, 140 insertions(+), 15 deletions(-) diff --git a/doc/src/sgml/gist.sgml b/doc/src/sgml/gist.sgml index 44a3b2c..e903319 100644 --- a/doc/src/sgml/gist.sgml +++ b/doc/src/sgml/gist.sgml @@ -83,6 +83,7 @@ <literal>~=</literal> </entry> <entry> + <literal><-></literal> </entry> </row> <row> diff --git a/src/backend/access/gist/gistproc.c b/src/backend/access/gist/gistproc.c index 1826b51..89bd656 100644 --- a/src/backend/access/gist/gistproc.c +++ b/src/backend/access/gist/gistproc.c @@ -1464,26 +1464,13 @@ gist_point_distance(PG_FUNCTION_ARGS) PG_RETURN_FLOAT8(distance); } -/* - * The inexact GiST distance method for geometric types that store bounding - * boxes. - * - * Compute lossy distance from point to index entries. The result is inexact - * because index entries are bounding boxes, not the exact shapes of the - * indexed geometric types. We use distance from point to MBR of index entry. - * This is a lower bound estimate of distance from point to indexed geometric - * type. - */ static float8 -gist_bbox_distance(GISTENTRY *entry, Datum query, - StrategyNumber strategy, bool *recheck) +gist_box_distance_helper(GISTENTRY *entry, Datum query, + StrategyNumber strategy) { float8 distance; StrategyNumber strategyGroup = strategy / GeoStrategyNumberOffset; - /* Bounding box distance is always inexact. */ - *recheck = true; - switch (strategyGroup) { case PointStrategyNumberGroup: @@ -1500,6 +1487,42 @@ gist_bbox_distance(GISTENTRY *entry, Datum query, } Datum +gist_box_distance(PG_FUNCTION_ARGS) +{ + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); + Datum query = PG_GETARG_DATUM(1); + StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2); + + /* Oid subtype = PG_GETARG_OID(3); */ + /* bool *recheck = (bool *) PG_GETARG_POINTER(4); */ + float8 distance; + + distance = gist_box_distance_helper(entry, query, strategy); + + PG_RETURN_FLOAT8(distance); +} + +/* + * The inexact GiST distance method for geometric types that store bounding + * boxes. + * + * Compute lossy distance from point to index entries. The result is inexact + * because index entries are bounding boxes, not the exact shapes of the + * indexed geometric types. We use distance from point to MBR of index entry. + * This is a lower bound estimate of distance from point to indexed geometric + * type. + */ +static float8 +gist_bbox_distance(GISTENTRY *entry, Datum query, + StrategyNumber strategy, bool *recheck) +{ + /* Bounding box distance is always inexact. */ + *recheck = true; + + return gist_box_distance_helper(entry, query, strategy); +} + +Datum gist_circle_distance(PG_FUNCTION_ARGS) { GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); diff --git a/src/include/catalog/pg_amop.dat b/src/include/catalog/pg_amop.dat index cf63eb7..ebc38ae 100644 --- a/src/include/catalog/pg_amop.dat +++ b/src/include/catalog/pg_amop.dat @@ -1081,6 +1081,9 @@ amopstrategy => '13', amopopr => '~(box,box)', amopmethod => 'gist' }, { amopfamily => 'gist/box_ops', amoplefttype => 'box', amoprighttype => 'box', amopstrategy => '14', amopopr => '@(box,box)', amopmethod => 'gist' }, +{ amopfamily => 'gist/box_ops', amoplefttype => 'box', amoprighttype => 'point', + amopstrategy => '15', amoppurpose => 'o', amopopr => '<->(box,point)', + amopmethod => 'gist', amopsortfamily => 'btree/float_ops' }, # gist point_ops { amopfamily => 'gist/point_ops', amoplefttype => 'point', diff --git a/src/include/catalog/pg_amproc.dat b/src/include/catalog/pg_amproc.dat index 020b741..5567b7e 100644 --- a/src/include/catalog/pg_amproc.dat +++ b/src/include/catalog/pg_amproc.dat @@ -419,6 +419,8 @@ amprocrighttype => 'box', amprocnum => '6', amproc => 'gist_box_picksplit' }, { amprocfamily => 'gist/box_ops', amproclefttype => 'box', amprocrighttype => 'box', amprocnum => '7', amproc => 'gist_box_same' }, +{ amprocfamily => 'gist/box_ops', amproclefttype => 'box', + amprocrighttype => 'box', amprocnum => '8', amproc => 'gist_box_distance' }, { amprocfamily => 'gist/poly_ops', amproclefttype => 'polygon', amprocrighttype => 'polygon', amprocnum => '1', amproc => 'gist_poly_consistent' }, diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 54327bf..d15f94a 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -7816,6 +7816,10 @@ { oid => '2584', descr => 'GiST support', proname => 'gist_box_same', prorettype => 'internal', proargtypes => 'box box internal', prosrc => 'gist_box_same' }, +{ oid => '3998', descr => 'GiST support', + proname => 'gist_box_distance', prorettype => 'float8', + proargtypes => 'internal box int2 oid internal', + prosrc => 'gist_box_distance' }, { oid => '2585', descr => 'GiST support', proname => 'gist_poly_consistent', prorettype => 'bool', proargtypes => 'internal polygon int2 oid internal', diff --git a/src/test/regress/expected/gist.out b/src/test/regress/expected/gist.out index 0a43449..2234876 100644 --- a/src/test/regress/expected/gist.out +++ b/src/test/regress/expected/gist.out @@ -203,6 +203,82 @@ select b from gist_tbl where b <@ box(point(5,5), point(6,6)); (6,6),(6,6) (21 rows) +-- Also test an index-only knn-search +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + QUERY PLAN +------------------------------------------------------ + Index Only Scan using gist_tbl_box_index on gist_tbl + Index Cond: (b <@ '(6,6),(5,5)'::box) + Order By: (b <-> '(5.2,5.91)'::point) +(3 rows) + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + b +------------------------- + (5.55,5.55),(5.55,5.55) + (5.6,5.6),(5.6,5.6) + (5.5,5.5),(5.5,5.5) + (5.65,5.65),(5.65,5.65) + (5.45,5.45),(5.45,5.45) + (5.7,5.7),(5.7,5.7) + (5.4,5.4),(5.4,5.4) + (5.75,5.75),(5.75,5.75) + (5.35,5.35),(5.35,5.35) + (5.8,5.8),(5.8,5.8) + (5.3,5.3),(5.3,5.3) + (5.85,5.85),(5.85,5.85) + (5.25,5.25),(5.25,5.25) + (5.9,5.9),(5.9,5.9) + (5.2,5.2),(5.2,5.2) + (5.95,5.95),(5.95,5.95) + (5.15,5.15),(5.15,5.15) + (6,6),(6,6) + (5.1,5.1),(5.1,5.1) + (5.05,5.05),(5.05,5.05) + (5,5),(5,5) +(21 rows) + +-- Check commuted case as well +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + QUERY PLAN +------------------------------------------------------ + Index Only Scan using gist_tbl_box_index on gist_tbl + Index Cond: (b <@ '(6,6),(5,5)'::box) + Order By: (b <-> '(5.2,5.91)'::point) +(3 rows) + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + b +------------------------- + (5.55,5.55),(5.55,5.55) + (5.6,5.6),(5.6,5.6) + (5.5,5.5),(5.5,5.5) + (5.65,5.65),(5.65,5.65) + (5.45,5.45),(5.45,5.45) + (5.7,5.7),(5.7,5.7) + (5.4,5.4),(5.4,5.4) + (5.75,5.75),(5.75,5.75) + (5.35,5.35),(5.35,5.35) + (5.8,5.8),(5.8,5.8) + (5.3,5.3),(5.3,5.3) + (5.85,5.85),(5.85,5.85) + (5.25,5.25),(5.25,5.25) + (5.9,5.9),(5.9,5.9) + (5.2,5.2),(5.2,5.2) + (5.95,5.95),(5.95,5.95) + (5.15,5.15),(5.15,5.15) + (6,6),(6,6) + (5.1,5.1),(5.1,5.1) + (5.05,5.05),(5.05,5.05) + (5,5),(5,5) +(21 rows) + drop index gist_tbl_box_index; -- Test that an index-only scan is not chosen, when the query involves the -- circle column (the circle opclass does not support index-only scans). diff --git a/src/test/regress/sql/gist.sql b/src/test/regress/sql/gist.sql index 657b195..b9d398e 100644 --- a/src/test/regress/sql/gist.sql +++ b/src/test/regress/sql/gist.sql @@ -109,6 +109,22 @@ select b from gist_tbl where b <@ box(point(5,5), point(6,6)); -- execute the same select b from gist_tbl where b <@ box(point(5,5), point(6,6)); +-- Also test an index-only knn-search +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by b <-> point(5.2, 5.91); + +-- Check commuted case as well +explain (costs off) +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + +select b from gist_tbl where b <@ box(point(5,5), point(6,6)) +order by point(5.2, 5.91) <-> b; + drop index gist_tbl_box_index; -- Test that an index-only scan is not chosen, when the query involves the -- 2.7.4 --------------07EE9595454874974EAD75E7 Content-Type: text/x-patch; name="0003-Add-operator-box-point-to-SP-GiST-box_ops-v02.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="0003-Add-operator-box-point-to-SP-GiST-box_ops-v02.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-02-16 21:24 Matthias van de Meent <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Matthias van de Meent @ 2022-02-16 21:24 UTC (permalink / raw) To: pgsql-hackers Hi, I noticed that effectively all indexes use the special region of a page to store some index-specific data on the page. In all cases I've noticed, this is a constant-sized struct, located at what is effectively a fixed offset from the end of the page; indicated on the page by pd_special; and accessed through PageGetSpecialPointer() (that is about equal to `page + page->pd_special` modulo typing and assertions). Seeing that these indexes effectively always use a constant-sized struct as the only data in the special region; why does this code depend on the pd_special pointer to retrieve their PageOpaque pointer? Wouldn't a constant offset off of (page), based on the size of the opaque structure and BLCKSZ, be enough? Sure, in assertion builds this also validates that pd_special indeed points in the bounds of the page, but PageGetSpecialPointer() does not validate that the struct itself is in the bounds of the page, so there's little guarantee that this is actually safe. Additionally, this introduces a layer of indirection that is not necessarily useful: for example the_bt_step_left code has no use for the page's header information other than that it contains the pd_special pointer (which is effectively always BLCKSZ - MAXALIGN(sizeof(opaque))). This introduces more data and ordering dependencies in the CPU, where this should be as simple as a constant offset over the base page pointer. Assuming there's no significant reason to _not_ to change this code to a constant offset off the page pointer and only relying on pd_special in asserts when retrieving the IndexPageOpaques, I propose the attached patches: 0001 adds a new macro PageGetSpecialOpaque(page, opaquedatatyp); which replaces PageGetSpecialPointer for constant sized special area structures, and sets up the SPGist, GIST and Gin index methods to use that instead of PageGetSpecialPointer. 0002 replaces manual PageGetSpecialPointer calls & casts in btree code with a new macro BTPageGetOpaque, which utilizes PageGetSpecialOpaque. 0003 does the same as 0002, but for hash indexes. A first good reason to do this is preventing further damage when a page is corrupted: if I can somehow overwrite pd_special, non-assert-enabled builds would start reading and writing at arbitrary offsets from the page pointer, quite possibly in subsequent buffers (or worse, on the stack, in case of stack-allocated blocks). A second reason would be less indirection to get to the opaque pointer. This should improve performance a bit in those cases where we (initially) only want to access the [Index]PageOpaque struct. Lastly, 0002 and 0003 remove some repetitive tasks of dealing with the [nbtree, hash] opaques by providing a typed accessor macro similar to what is used in the GIN and (SP-)GIST index methods; improving the legibility of the code and decreasing the churn. Kind regards, Matthias van de Meent. Attachments: [application/octet-stream] v1-0001-Add-known-size-pre-aligned-special-area-pointer-m.patch (4.0K, ../../CAEze2WjE3+tGO9Fs9+iZMU+z6mMZKo54W1Zt98WKqbEUHbHOBg@mail.gmail.com/2-v1-0001-Add-known-size-pre-aligned-special-area-pointer-m.patch) download | inline diff: From c6191d6c52de2604d7809e5216858d5296969778 Mon Sep 17 00:00:00 2001 From: Matthias van de Meent <[email protected]> Date: Wed, 16 Feb 2022 00:55:24 +0100 Subject: [PATCH v1 1/3] Add known-size pre-aligned special area pointer macro This removes 1 layer of indirection for special areas of which we know the type (=size) and location. Special area access through the page header is an extra cache line that needs to be fetched. If might only want to look at the special area, it is much less effort to calculate the offset to the special area directly instead of first checking the page header - saving one cache line to fetch. Assertions are added to check that the page has a correctly sized special area, and that the page is of the expected size. This detects data corruption, instead of doing random reads/writes into the page or data allocated next to the page being accessed. Additionally, updates the GIN, GIST and SP-GIST [Index]PageGetOpaque macros with the new pre-aligned special area accessor. --- src/include/access/ginblock.h | 3 ++- src/include/access/gist.h | 3 ++- src/include/access/spgist_private.h | 3 ++- src/include/storage/bufpage.h | 13 +++++++++++++ 4 files changed, 19 insertions(+), 3 deletions(-) diff --git a/src/include/access/ginblock.h b/src/include/access/ginblock.h index 9347f464f3..9c2af08a27 100644 --- a/src/include/access/ginblock.h +++ b/src/include/access/ginblock.h @@ -108,7 +108,8 @@ typedef struct GinMetaPageData /* * Macros for accessing a GIN index page's opaque data */ -#define GinPageGetOpaque(page) ( (GinPageOpaque) PageGetSpecialPointer(page) ) +#define GinPageGetOpaque(page) \ + ( (GinPageOpaque) PageGetSpecialOpaque(page, GinPageOpaqueData) ) #define GinPageIsLeaf(page) ( (GinPageGetOpaque(page)->flags & GIN_LEAF) != 0 ) #define GinPageSetLeaf(page) ( GinPageGetOpaque(page)->flags |= GIN_LEAF ) diff --git a/src/include/access/gist.h b/src/include/access/gist.h index a3337627b8..987f771c4d 100644 --- a/src/include/access/gist.h +++ b/src/include/access/gist.h @@ -164,7 +164,8 @@ typedef struct GISTENTRY bool leafkey; } GISTENTRY; -#define GistPageGetOpaque(page) ( (GISTPageOpaque) PageGetSpecialPointer(page) ) +#define GistPageGetOpaque(page) \ + ( (GISTPageOpaque) PageGetSpecialOpaque(page, GISTPageOpaqueData) ) #define GistPageIsLeaf(page) ( GistPageGetOpaque(page)->flags & F_LEAF) #define GIST_LEAF(entry) (GistPageIsLeaf((entry)->page)) diff --git a/src/include/access/spgist_private.h b/src/include/access/spgist_private.h index eb56b1c6b8..b0bdc7df3e 100644 --- a/src/include/access/spgist_private.h +++ b/src/include/access/spgist_private.h @@ -75,7 +75,8 @@ typedef SpGistPageOpaqueData *SpGistPageOpaque; #define SPGIST_LEAF (1<<2) #define SPGIST_NULLS (1<<3) -#define SpGistPageGetOpaque(page) ((SpGistPageOpaque) PageGetSpecialPointer(page)) +#define SpGistPageGetOpaque(page) \ + ((SpGistPageOpaque) PageGetSpecialOpaque(page, SpGistPageOpaqueData)) #define SpGistPageIsMeta(page) (SpGistPageGetOpaque(page)->flags & SPGIST_META) #define SpGistPageIsDeleted(page) (SpGistPageGetOpaque(page)->flags & SPGIST_DELETED) #define SpGistPageIsLeaf(page) (SpGistPageGetOpaque(page)->flags & SPGIST_LEAF) diff --git a/src/include/storage/bufpage.h b/src/include/storage/bufpage.h index e9f253f2c8..aa395d3c39 100644 --- a/src/include/storage/bufpage.h +++ b/src/include/storage/bufpage.h @@ -329,6 +329,19 @@ PageValidateSpecialPointer(Page page) (char *) ((char *) (page) + ((PageHeader) (page))->pd_special) \ ) +/* + * PageGetSpecialOpaque + * Returns pointer to special space on a page, of the given type. + * This removes the data dependency on the page header in builds + * without asserts enabled. + */ +#define PageGetSpecialOpaque(page, OpaqueDataTyp) \ +( \ + AssertMacro(PageGetPageSize(page) == BLCKSZ && \ + PageGetSpecialSize(page) == MAXALIGN(sizeof(OpaqueDataTyp))), \ + (OpaqueDataTyp *) ((char *) (page) + (BLCKSZ - MAXALIGN(sizeof(OpaqueDataTyp)))) \ +) + /* * PageGetItem * Retrieves an item on the given page. -- 2.30.2 [application/octet-stream] v1-0003-Update-hash-code-to-use-PageGetSpecialOpaque-repl.patch (22.5K, ../../CAEze2WjE3+tGO9Fs9+iZMU+z6mMZKo54W1Zt98WKqbEUHbHOBg@mail.gmail.com/3-v1-0003-Update-hash-code-to-use-PageGetSpecialOpaque-repl.patch) download | inline diff: From e9136b78c3beac355122d9ca7721a7f4ef2f2c1e Mon Sep 17 00:00:00 2001 From: Matthias van de Meent <[email protected]> Date: Wed, 16 Feb 2022 01:01:29 +0100 Subject: [PATCH v1 3/3] Update hash code to use PageGetSpecialOpaque; replace cast+macro As in the earlier patch, this reduces memory access requirements by directly reading into the target space instead of needing to access the header of the page first. Also makes the code a lot more readable by replacing templated macro+casts with a single macro specialized for hash page opaques. --- contrib/pageinspect/hashfuncs.c | 6 +++--- contrib/pgstattuple/pgstatindex.c | 2 +- contrib/pgstattuple/pgstattuple.c | 2 +- src/backend/access/hash/hash.c | 6 +++--- src/backend/access/hash/hash_xlog.c | 26 ++++++++++++------------ src/backend/access/hash/hashinsert.c | 6 +++--- src/backend/access/hash/hashovfl.c | 22 ++++++++++---------- src/backend/access/hash/hashpage.c | 30 ++++++++++++++-------------- src/backend/access/hash/hashsearch.c | 12 +++++------ src/backend/access/hash/hashutil.c | 4 ++-- src/include/access/hash.h | 3 +++ 11 files changed, 61 insertions(+), 58 deletions(-) diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c index 090eba4a93..313c8ee252 100644 --- a/contrib/pageinspect/hashfuncs.c +++ b/contrib/pageinspect/hashfuncs.c @@ -69,7 +69,7 @@ verify_hash_page(bytea *raw_page, int flags) (errcode(ERRCODE_INDEX_CORRUPTED), errmsg("index table contains corrupted page"))); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); if (pageopaque->hasho_page_id != HASHO_PAGE_ID) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), @@ -151,7 +151,7 @@ static void GetHashPageStatistics(Page page, HashPageStat *stat) { OffsetNumber maxoff = PageGetMaxOffsetNumber(page); - HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page); + HashPageOpaque opaque = HashPageGetOpaque(page); int off; stat->dead_items = stat->live_items = 0; @@ -203,7 +203,7 @@ hash_page_type(PG_FUNCTION_ARGS) type = "unused"; else { - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); /* page type (flags) */ pagetype = opaque->hasho_flag & LH_PAGE_TYPE; diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c index b9939451b4..e1048e47ff 100644 --- a/contrib/pgstattuple/pgstatindex.c +++ b/contrib/pgstattuple/pgstatindex.c @@ -641,7 +641,7 @@ pgstathashindex(PG_FUNCTION_ARGS) HashPageOpaque opaque; int pagetype; - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); pagetype = opaque->hasho_flag & LH_PAGE_TYPE; if (pagetype == LH_BUCKET_PAGE) diff --git a/contrib/pgstattuple/pgstattuple.c b/contrib/pgstattuple/pgstattuple.c index a9658d389b..3094566908 100644 --- a/contrib/pgstattuple/pgstattuple.c +++ b/contrib/pgstattuple/pgstattuple.c @@ -452,7 +452,7 @@ pgstat_hash_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno, { HashPageOpaque opaque; - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); switch (opaque->hasho_flag & LH_PAGE_TYPE) { case LH_UNUSED_PAGE: diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c index a259a301fa..fd1a7119b6 100644 --- a/src/backend/access/hash/hash.c +++ b/src/backend/access/hash/hash.c @@ -515,7 +515,7 @@ loop_top: _hash_checkpage(rel, buf, LH_BUCKET_PAGE); page = BufferGetPage(buf); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); /* * If the bucket contains tuples that are moved by split, then we need @@ -717,7 +717,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf, vacuum_delay_point(); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); /* Scan each tuple in page */ maxoffno = PageGetMaxOffsetNumber(page); @@ -884,7 +884,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf, Page page; page = BufferGetPage(bucket_buf); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); /* No ereport(ERROR) until changes are logged */ START_CRIT_SECTION(); diff --git a/src/backend/access/hash/hash_xlog.c b/src/backend/access/hash/hash_xlog.c index 55937b9a68..62dbfc3a5d 100644 --- a/src/backend/access/hash/hash_xlog.c +++ b/src/backend/access/hash/hash_xlog.c @@ -203,7 +203,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record) true); /* update backlink */ ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = leftblk; PageSetLSN(ovflpage, lsn); @@ -215,7 +215,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record) HashPageOpaque leftopaque; leftpage = BufferGetPage(leftbuf); - leftopaque = (HashPageOpaque) PageGetSpecialPointer(leftpage); + leftopaque = HashPageGetOpaque(leftpage); leftopaque->hasho_nextblkno = rightblk; PageSetLSN(leftpage, lsn); @@ -342,7 +342,7 @@ hash_xlog_split_allocate_page(XLogReaderState *record) HashPageOpaque oldopaque; oldpage = BufferGetPage(oldbuf); - oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage); + oldopaque = HashPageGetOpaque(oldpage); oldopaque->hasho_flag = xlrec->old_bucket_flag; oldopaque->hasho_prevblkno = xlrec->new_bucket; @@ -465,7 +465,7 @@ hash_xlog_split_complete(XLogReaderState *record) HashPageOpaque oldopaque; oldpage = BufferGetPage(oldbuf); - oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage); + oldopaque = HashPageGetOpaque(oldpage); oldopaque->hasho_flag = xlrec->old_bucket_flag; @@ -488,7 +488,7 @@ hash_xlog_split_complete(XLogReaderState *record) HashPageOpaque nopaque; newpage = BufferGetPage(newbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(newpage); + nopaque = HashPageGetOpaque(newpage); nopaque->hasho_flag = xlrec->new_bucket_flag; @@ -710,7 +710,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) */ if (xldata->is_prev_bucket_same_wrt) { - HashPageOpaque writeopaque = (HashPageOpaque) PageGetSpecialPointer(writepage); + HashPageOpaque writeopaque = HashPageGetOpaque(writepage); writeopaque->hasho_nextblkno = xldata->nextblkno; } @@ -729,7 +729,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) _hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf)); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -748,7 +748,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) XLogReadBufferForRedo(record, 3, &prevbuf) == BLK_NEEDS_REDO) { Page prevpage = BufferGetPage(prevbuf); - HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage); + HashPageOpaque prevopaque = HashPageGetOpaque(prevpage); prevopaque->hasho_nextblkno = xldata->nextblkno; @@ -766,7 +766,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) if (XLogReadBufferForRedo(record, 4, &nextbuf) == BLK_NEEDS_REDO) { Page nextpage = BufferGetPage(nextbuf); - HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage); + HashPageOpaque nextopaque = HashPageGetOpaque(nextpage); nextopaque->hasho_prevblkno = xldata->prevblkno; @@ -903,7 +903,7 @@ hash_xlog_delete(XLogReaderState *record) { HashPageOpaque pageopaque; - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; } @@ -933,7 +933,7 @@ hash_xlog_split_cleanup(XLogReaderState *record) page = (Page) BufferGetPage(buffer); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); bucket_opaque->hasho_flag &= ~LH_BUCKET_NEEDS_SPLIT_CLEANUP; PageSetLSN(page, lsn); MarkBufferDirty(buffer); @@ -1024,7 +1024,7 @@ hash_xlog_vacuum_one_page(XLogReaderState *record) * Mark the page as not containing any LP_DEAD items. See comments in * _hash_vacuum_one_page() for details. */ - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; PageSetLSN(page, lsn); @@ -1116,7 +1116,7 @@ hash_mask(char *pagedata, BlockNumber blkno) mask_page_hint_bits(page); mask_unused_space(page); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); pagetype = opaque->hasho_flag & LH_PAGE_TYPE; if (pagetype == LH_UNUSED_PAGE) diff --git a/src/backend/access/hash/hashinsert.c b/src/backend/access/hash/hashinsert.c index faf609c157..4f2fecb908 100644 --- a/src/backend/access/hash/hashinsert.c +++ b/src/backend/access/hash/hashinsert.c @@ -95,7 +95,7 @@ restart_insert: bucket_buf = buf; page = BufferGetPage(buf); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); bucket = pageopaque->hasho_bucket; /* @@ -183,7 +183,7 @@ restart_insert: /* should fit now, given test above */ Assert(PageGetFreeSpace(page) >= itemsz); } - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); Assert((pageopaque->hasho_flag & LH_PAGE_TYPE) == LH_OVERFLOW_PAGE); Assert(pageopaque->hasho_bucket == bucket); } @@ -384,7 +384,7 @@ _hash_vacuum_one_page(Relation rel, Relation hrel, Buffer metabuf, Buffer buf) * check it. Remember that LH_PAGE_HAS_DEAD_TUPLES is only a hint * anyway. */ - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; metap = HashPageGetMeta(BufferGetPage(metabuf)); diff --git a/src/backend/access/hash/hashovfl.c b/src/backend/access/hash/hashovfl.c index 4836875196..e34cfc302d 100644 --- a/src/backend/access/hash/hashovfl.c +++ b/src/backend/access/hash/hashovfl.c @@ -159,7 +159,7 @@ _hash_addovflpage(Relation rel, Buffer metabuf, Buffer buf, bool retain_pin) BlockNumber nextblkno; page = BufferGetPage(buf); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); nextblkno = pageopaque->hasho_nextblkno; if (!BlockNumberIsValid(nextblkno)) @@ -364,7 +364,7 @@ found: /* initialize new overflow page */ ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = BufferGetBlockNumber(buf); ovflopaque->hasho_nextblkno = InvalidBlockNumber; ovflopaque->hasho_bucket = pageopaque->hasho_bucket; @@ -516,7 +516,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, _hash_checkpage(rel, ovflbuf, LH_OVERFLOW_PAGE); ovflblkno = BufferGetBlockNumber(ovflbuf); ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); nextblkno = ovflopaque->hasho_nextblkno; prevblkno = ovflopaque->hasho_prevblkno; writeblkno = BufferGetBlockNumber(wbuf); @@ -600,7 +600,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, */ _hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf)); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -613,7 +613,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, if (BufferIsValid(prevbuf)) { Page prevpage = BufferGetPage(prevbuf); - HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage); + HashPageOpaque prevopaque = HashPageGetOpaque(prevpage); Assert(prevopaque->hasho_bucket == bucket); prevopaque->hasho_nextblkno = nextblkno; @@ -622,7 +622,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, if (BufferIsValid(nextbuf)) { Page nextpage = BufferGetPage(nextbuf); - HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage); + HashPageOpaque nextopaque = HashPageGetOpaque(nextpage); Assert(nextopaque->hasho_bucket == bucket); nextopaque->hasho_prevblkno = prevblkno; @@ -751,7 +751,7 @@ _hash_initbitmapbuffer(Buffer buf, uint16 bmsize, bool initpage) _hash_pageinit(pg, BufferGetPageSize(buf)); /* initialize the page's special space */ - op = (HashPageOpaque) PageGetSpecialPointer(pg); + op = HashPageGetOpaque(pg); op->hasho_prevblkno = InvalidBlockNumber; op->hasho_nextblkno = InvalidBlockNumber; op->hasho_bucket = InvalidBucket; @@ -824,7 +824,7 @@ _hash_squeezebucket(Relation rel, wblkno = bucket_blkno; wbuf = bucket_buf; wpage = BufferGetPage(wbuf); - wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage); + wopaque = HashPageGetOpaque(wpage); /* * if there aren't any overflow pages, there's nothing to squeeze. caller @@ -855,7 +855,7 @@ _hash_squeezebucket(Relation rel, LH_OVERFLOW_PAGE, bstrategy); rpage = BufferGetPage(rbuf); - ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage); + ropaque = HashPageGetOpaque(rpage); Assert(ropaque->hasho_bucket == bucket); } while (BlockNumberIsValid(ropaque->hasho_nextblkno)); @@ -1005,7 +1005,7 @@ readpage: wbuf = next_wbuf; wpage = BufferGetPage(wbuf); - wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage); + wopaque = HashPageGetOpaque(wpage); Assert(wopaque->hasho_bucket == bucket); retain_pin = false; @@ -1076,7 +1076,7 @@ readpage: LH_OVERFLOW_PAGE, bstrategy); rpage = BufferGetPage(rbuf); - ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage); + ropaque = HashPageGetOpaque(rpage); Assert(ropaque->hasho_bucket == bucket); } diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c index 28c5297a1d..39206d1942 100644 --- a/src/backend/access/hash/hashpage.c +++ b/src/backend/access/hash/hashpage.c @@ -166,7 +166,7 @@ _hash_initbuf(Buffer buf, uint32 max_bucket, uint32 num_bucket, uint32 flag, if (initpage) _hash_pageinit(page, BufferGetPageSize(buf)); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); /* * Set hasho_prevblkno with current hashm_maxbucket. This value will be @@ -529,7 +529,7 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid, if (initpage) _hash_pageinit(page, BufferGetPageSize(buf)); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_prevblkno = InvalidBlockNumber; pageopaque->hasho_nextblkno = InvalidBlockNumber; pageopaque->hasho_bucket = InvalidBucket; @@ -693,7 +693,7 @@ restart_expand: goto fail; opage = BufferGetPage(buf_oblkno); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); /* * We want to finish the split from a bucket as there is no apparent @@ -864,7 +864,7 @@ restart_expand: lowmask = metap->hashm_lowmask; opage = BufferGetPage(buf_oblkno); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); /* * Mark the old bucket to indicate that split is in progress. (At @@ -883,7 +883,7 @@ restart_expand: * initialize the new bucket's primary page and mark it to indicate that * split is in progress. */ - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); nopaque->hasho_prevblkno = maxbucket; nopaque->hasho_nextblkno = InvalidBlockNumber; nopaque->hasho_bucket = new_bucket; @@ -1010,7 +1010,7 @@ _hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks) */ _hash_pageinit(page, BLCKSZ); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(page); + ovflopaque = HashPageGetOpaque(page); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -1091,11 +1091,11 @@ _hash_splitbucket(Relation rel, bucket_obuf = obuf; opage = BufferGetPage(obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); bucket_nbuf = nbuf; npage = BufferGetPage(nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); /* Copy the predicate locks from old bucket to new bucket. */ PredicateLockPageSplit(rel, @@ -1198,7 +1198,7 @@ _hash_splitbucket(Relation rel, /* chain to a new overflow page */ nbuf = _hash_addovflpage(rel, metabuf, nbuf, (nbuf == bucket_nbuf)); npage = BufferGetPage(nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); } itups[nitups++] = new_itup; @@ -1251,7 +1251,7 @@ _hash_splitbucket(Relation rel, /* Else, advance to next old page */ obuf = _hash_getbuf(rel, oblkno, HASH_READ, LH_OVERFLOW_PAGE); opage = BufferGetPage(obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); } /* @@ -1264,11 +1264,11 @@ _hash_splitbucket(Relation rel, */ LockBuffer(bucket_obuf, BUFFER_LOCK_EXCLUSIVE); opage = BufferGetPage(bucket_obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); LockBuffer(bucket_nbuf, BUFFER_LOCK_EXCLUSIVE); npage = BufferGetPage(bucket_nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); START_CRIT_SECTION(); @@ -1392,7 +1392,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket, bucket_nbuf = nbuf; npage = BufferGetPage(nbuf); - npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + npageopaque = HashPageGetOpaque(npage); /* Scan each tuple in new page */ nmaxoffnum = PageGetMaxOffsetNumber(npage); @@ -1446,7 +1446,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket, } npage = BufferGetPage(bucket_nbuf); - npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + npageopaque = HashPageGetOpaque(npage); nbucket = npageopaque->hasho_bucket; _hash_splitbucket(rel, metabuf, obucket, @@ -1587,7 +1587,7 @@ _hash_getbucketbuf_from_hashkey(Relation rel, uint32 hashkey, int access, /* Fetch the primary bucket page for the bucket */ buf = _hash_getbuf(rel, blkno, access, LH_BUCKET_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); Assert(opaque->hasho_bucket == bucket); Assert(opaque->hasho_prevblkno != InvalidBlockNumber); diff --git a/src/backend/access/hash/hashsearch.c b/src/backend/access/hash/hashsearch.c index 7ca542a3fb..524af27409 100644 --- a/src/backend/access/hash/hashsearch.c +++ b/src/backend/access/hash/hashsearch.c @@ -187,7 +187,7 @@ _hash_readnext(IndexScanDesc scan, { *pagep = BufferGetPage(*bufp); TestForOldSnapshot(scan->xs_snapshot, rel, *pagep); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); } } @@ -233,7 +233,7 @@ _hash_readprev(IndexScanDesc scan, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE); *pagep = BufferGetPage(*bufp); TestForOldSnapshot(scan->xs_snapshot, rel, *pagep); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); /* * We always maintain the pin on bucket page for whole scan operation, @@ -258,7 +258,7 @@ _hash_readprev(IndexScanDesc scan, LockBuffer(*bufp, BUFFER_LOCK_SHARE); *pagep = BufferGetPage(*bufp); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); /* move to the end of bucket chain */ while (BlockNumberIsValid((*opaquep)->hasho_nextblkno)) @@ -352,7 +352,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir) PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot); page = BufferGetPage(buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); bucket = opaque->hasho_bucket; so->hashso_bucket_buf = buf; @@ -398,7 +398,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir) LockBuffer(buf, BUFFER_LOCK_SHARE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); Assert(opaque->hasho_bucket == bucket); if (H_BUCKET_BEING_POPULATED(opaque)) @@ -463,7 +463,7 @@ _hash_readpage(IndexScanDesc scan, Buffer *bufP, ScanDirection dir) Assert(BufferIsValid(buf)); _hash_checkpage(rel, buf, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); so->currPos.buf = buf; so->currPos.currPage = BufferGetBlockNumber(buf); diff --git a/src/backend/access/hash/hashutil.c b/src/backend/access/hash/hashutil.c index edb6fa968f..fe37bc47cb 100644 --- a/src/backend/access/hash/hashutil.c +++ b/src/backend/access/hash/hashutil.c @@ -239,7 +239,7 @@ _hash_checkpage(Relation rel, Buffer buf, int flags) if (flags) { - HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page); + HashPageOpaque opaque = HashPageGetOpaque(page); if ((opaque->hasho_flag & flags) == 0) ereport(ERROR, @@ -574,7 +574,7 @@ _hash_kill_items(IndexScanDesc scan) buf = _hash_getbuf(rel, blkno, HASH_READ, LH_OVERFLOW_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); for (i = 0; i < numKilled; i++) diff --git a/src/include/access/hash.h b/src/include/access/hash.h index cd7b2a53d8..d3fd8bf239 100644 --- a/src/include/access/hash.h +++ b/src/include/access/hash.h @@ -85,6 +85,9 @@ typedef struct HashPageOpaqueData typedef HashPageOpaqueData *HashPageOpaque; +#define HashPageGetOpaque(page) \ + ((HashPageOpaque) PageGetSpecialOpaque((page), HashPageOpaqueData)) + #define H_NEEDS_SPLIT_CLEANUP(opaque) (((opaque)->hasho_flag & LH_BUCKET_NEEDS_SPLIT_CLEANUP) != 0) #define H_BUCKET_BEING_SPLIT(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_SPLIT) != 0) #define H_BUCKET_BEING_POPULATED(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_POPULATED) != 0) -- 2.30.2 [application/octet-stream] v1-0002-Update-nbtree-code-to-use-PageGetSpecialOpaque-re.patch (44.6K, ../../CAEze2WjE3+tGO9Fs9+iZMU+z6mMZKo54W1Zt98WKqbEUHbHOBg@mail.gmail.com/4-v1-0002-Update-nbtree-code-to-use-PageGetSpecialOpaque-re.patch) download | inline diff: From 2784b1e6365b8f755d815e5354bc00f693c1b75a Mon Sep 17 00:00:00 2001 From: Matthias van de Meent <[email protected]> Date: Wed, 16 Feb 2022 00:59:50 +0100 Subject: [PATCH v1 2/3] Update nbtree code to use PageGetSpecialOpaque; replace cast+macro As in the earlier patch, this reduces memory access requirements by directly reading into the target space instead of needing to access the header of the page first. Also makes the code a lot more readable by replacing templated macro+casts with a single macro specialized for BTree page opaques. --- contrib/amcheck/verify_nbtree.c | 32 +++++++------- contrib/pageinspect/btreefuncs.c | 6 +-- contrib/pgstattuple/pgstatindex.c | 2 +- contrib/pgstattuple/pgstattuple.c | 2 +- src/backend/access/nbtree/nbtdedup.c | 6 +-- src/backend/access/nbtree/nbtinsert.c | 46 ++++++++++---------- src/backend/access/nbtree/nbtpage.c | 58 ++++++++++++------------- src/backend/access/nbtree/nbtree.c | 2 +- src/backend/access/nbtree/nbtsearch.c | 34 +++++++-------- src/backend/access/nbtree/nbtsort.c | 12 ++--- src/backend/access/nbtree/nbtsplitloc.c | 2 +- src/backend/access/nbtree/nbtutils.c | 6 +-- src/backend/access/nbtree/nbtxlog.c | 34 +++++++-------- src/include/access/nbtree.h | 13 ++++-- 14 files changed, 131 insertions(+), 124 deletions(-) diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c index d2510ee648..70278c4f93 100644 --- a/contrib/amcheck/verify_nbtree.c +++ b/contrib/amcheck/verify_nbtree.c @@ -691,7 +691,7 @@ bt_check_level_from_leftmost(BtreeCheckState *state, BtreeLevel level) state->target = palloc_btree_page(state, state->targetblock); state->targetlsn = PageGetLSN(state->target); - opaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + opaque = BTPageGetOpaque(state->target); if (P_IGNORE(opaque)) { @@ -927,7 +927,7 @@ bt_recheck_sibling_links(BtreeCheckState *state, LockBuffer(lbuf, BT_READ); _bt_checkpage(state->rel, lbuf); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* @@ -951,7 +951,7 @@ bt_recheck_sibling_links(BtreeCheckState *state, LockBuffer(newtargetbuf, BT_READ); _bt_checkpage(state->rel, newtargetbuf); page = BufferGetPage(newtargetbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* btpo_prev_from_target may have changed; update it */ btpo_prev_from_target = opaque->btpo_prev; } @@ -1049,7 +1049,7 @@ bt_target_page_check(BtreeCheckState *state) OffsetNumber max; BTPageOpaque topaque; - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); max = PageGetMaxOffsetNumber(state->target); elog(DEBUG2, "verifying %u items on %s block %u", max, @@ -1478,7 +1478,7 @@ bt_target_page_check(BtreeCheckState *state) /* Get fresh copy of target page */ state->target = palloc_btree_page(state, state->targetblock); /* Note that we deliberately do not update target LSN */ - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); /* * All !readonly checks now performed; just return @@ -1552,7 +1552,7 @@ bt_right_page_check_scankey(BtreeCheckState *state) OffsetNumber nline; /* Determine target's next block number */ - opaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + opaque = BTPageGetOpaque(state->target); /* If target is already rightmost, no right sibling; nothing to do here */ if (P_RIGHTMOST(opaque)) @@ -1588,7 +1588,7 @@ bt_right_page_check_scankey(BtreeCheckState *state) CHECK_FOR_INTERRUPTS(); rightpage = palloc_btree_page(state, targetnext); - opaque = (BTPageOpaque) PageGetSpecialPointer(rightpage); + opaque = BTPageGetOpaque(rightpage); if (!P_IGNORE(opaque) || P_RIGHTMOST(opaque)) break; @@ -1893,7 +1893,7 @@ bt_child_highkey_check(BtreeCheckState *state, else page = palloc_btree_page(state, blkno); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* The first page we visit at the level should be leftmost */ if (first && !BlockNumberIsValid(state->prevrightlink) && !P_LEFTMOST(opaque)) @@ -1971,7 +1971,7 @@ bt_child_highkey_check(BtreeCheckState *state, else pivotkey_offset = target_downlinkoffnum; - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); if (!offset_is_negative_infinity(topaque, pivotkey_offset)) { @@ -2128,9 +2128,9 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey, * Check all items, rather than checking just the first and trusting that * the operator class obeys the transitive law. */ - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); child = palloc_btree_page(state, childblock); - copaque = (BTPageOpaque) PageGetSpecialPointer(child); + copaque = BTPageGetOpaque(child); maxoffset = PageGetMaxOffsetNumber(child); /* @@ -2235,7 +2235,7 @@ static void bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit, BlockNumber blkno, Page page) { - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); ItemId itemid; IndexTuple itup; Page child; @@ -2319,7 +2319,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit, CHECK_FOR_INTERRUPTS(); child = palloc_btree_page(state, childblk); - copaque = (BTPageOpaque) PageGetSpecialPointer(child); + copaque = BTPageGetOpaque(child); if (P_ISLEAF(copaque)) break; @@ -2780,7 +2780,7 @@ invariant_l_offset(BtreeCheckState *state, BTScanInsert key, bool nonpivot; ritup = (IndexTuple) PageGetItem(state->target, itemid); - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); nonpivot = P_ISLEAF(topaque) && upperbound >= P_FIRSTDATAKEY(topaque); /* Get number of keys + heap TID for item to the right */ @@ -2895,7 +2895,7 @@ invariant_l_nontarget_offset(BtreeCheckState *state, BTScanInsert key, bool nonpivot; child = (IndexTuple) PageGetItem(nontarget, itemid); - copaque = (BTPageOpaque) PageGetSpecialPointer(nontarget); + copaque = BTPageGetOpaque(nontarget); nonpivot = P_ISLEAF(copaque) && upperbound >= P_FIRSTDATAKEY(copaque); /* Get number of keys + heap TID for child/non-target item */ @@ -2954,7 +2954,7 @@ palloc_btree_page(BtreeCheckState *state, BlockNumber blocknum) memcpy(page, BufferGetPage(buffer), BLCKSZ); UnlockReleaseBuffer(buffer); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISMETA(opaque) && blocknum != BTREE_METAPAGE) ereport(ERROR, diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c index 03debe336b..4aaff114c6 100644 --- a/contrib/pageinspect/btreefuncs.c +++ b/contrib/pageinspect/btreefuncs.c @@ -93,7 +93,7 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat) Page page = BufferGetPage(buffer); PageHeader phdr = (PageHeader) page; OffsetNumber maxoff = PageGetMaxOffsetNumber(page); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); int item_size = 0; int off; @@ -521,7 +521,7 @@ bt_page_items_internal(PG_FUNCTION_ARGS, enum pageinspect_version ext_version) uargs->offset = FirstOffsetNumber; - opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page); + opaque = BTPageGetOpaque(uargs->page); if (!P_ISDELETED(opaque)) fctx->max_calls = PageGetMaxOffsetNumber(uargs->page); @@ -617,7 +617,7 @@ bt_page_items_bytea(PG_FUNCTION_ARGS) uargs->offset = FirstOffsetNumber; - opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page); + opaque = BTPageGetOpaque(uargs->page); if (P_ISMETA(opaque)) ereport(ERROR, diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c index 6c4b053dd0..b9939451b4 100644 --- a/contrib/pgstattuple/pgstatindex.c +++ b/contrib/pgstattuple/pgstatindex.c @@ -281,7 +281,7 @@ pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo) LockBuffer(buffer, BUFFER_LOCK_SHARE); page = BufferGetPage(buffer); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Determine page type, and update totals. diff --git a/contrib/pgstattuple/pgstattuple.c b/contrib/pgstattuple/pgstattuple.c index c9b8f01f9b..a9658d389b 100644 --- a/contrib/pgstattuple/pgstattuple.c +++ b/contrib/pgstattuple/pgstattuple.c @@ -415,7 +415,7 @@ pgstat_btree_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno, { BTPageOpaque opaque; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_IGNORE(opaque)) { /* deleted or half-dead page */ diff --git a/src/backend/access/nbtree/nbtdedup.c b/src/backend/access/nbtree/nbtdedup.c index 4c48554aec..3e11805293 100644 --- a/src/backend/access/nbtree/nbtdedup.c +++ b/src/backend/access/nbtree/nbtdedup.c @@ -62,7 +62,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem, minoff, maxoff; Page page = BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); Page newpage; BTDedupState state; Size pagesaving = 0; @@ -231,7 +231,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem, */ if (P_HAS_GARBAGE(opaque)) { - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage); + BTPageOpaque nopaque = BTPageGetOpaque(newpage); nopaque->btpo_flags &= ~BTP_HAS_GARBAGE; } @@ -310,7 +310,7 @@ _bt_bottomupdel_pass(Relation rel, Buffer buf, Relation heapRel, minoff, maxoff; Page page = BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); BTDedupState state; TM_IndexDeleteOp delstate; bool neverdedup; diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c index 68628ec000..f6f4af8bfe 100644 --- a/src/backend/access/nbtree/nbtinsert.c +++ b/src/backend/access/nbtree/nbtinsert.c @@ -329,7 +329,7 @@ _bt_search_insert(Relation rel, BTInsertState insertstate) _bt_checkpage(rel, insertstate->buf); page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Check if the page is still the rightmost leaf page and has @@ -428,7 +428,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel, InitDirtySnapshot(SnapshotDirty); page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); /* @@ -733,7 +733,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel, nbuf = _bt_relandgetbuf(rel, nbuf, nblkno, BT_READ); page = BufferGetPage(nbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_IGNORE(opaque)) break; if (P_RIGHTMOST(opaque)) @@ -822,7 +822,7 @@ _bt_findinsertloc(Relation rel, BTPageOpaque opaque; OffsetNumber newitemoff; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Check 1/3 of a page restriction */ if (unlikely(insertstate->itemsz > BTMaxItemSize(page))) @@ -888,7 +888,7 @@ _bt_findinsertloc(Relation rel, _bt_stepright(rel, insertstate, stack); /* Update local state after stepping right */ page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Assume duplicates (if checkingunique) */ uniquedup = true; } @@ -972,7 +972,7 @@ _bt_findinsertloc(Relation rel, _bt_stepright(rel, insertstate, stack); /* Update local state after stepping right */ page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } } @@ -1030,7 +1030,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack) BlockNumber rblkno; page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); rbuf = InvalidBuffer; rblkno = opaque->btpo_next; @@ -1038,7 +1038,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack) { rbuf = _bt_relandgetbuf(rel, rbuf, rblkno, BT_WRITE); page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If this page was incompletely split, finish the split now. We do @@ -1120,7 +1120,7 @@ _bt_insertonpg(Relation rel, IndexTuple nposting = NULL; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); isleaf = P_ISLEAF(opaque); isroot = P_ISROOT(opaque); isrightmost = P_RIGHTMOST(opaque); @@ -1296,7 +1296,7 @@ _bt_insertonpg(Relation rel, if (!isleaf) { Page cpage = BufferGetPage(cbuf); - BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage); + BTPageOpaque cpageop = BTPageGetOpaque(cpage); Assert(P_INCOMPLETE_SPLIT(cpageop)); cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; @@ -1504,7 +1504,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, * only workspace. */ origpage = BufferGetPage(buf); - oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + oopaque = BTPageGetOpaque(origpage); isleaf = P_ISLEAF(oopaque); isrightmost = P_RIGHTMOST(oopaque); maxoff = PageGetMaxOffsetNumber(origpage); @@ -1540,7 +1540,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, /* Allocate temp buffer for leftpage */ leftpage = PageGetTempPage(origpage); _bt_pageinit(leftpage, BufferGetPageSize(buf)); - lopaque = (BTPageOpaque) PageGetSpecialPointer(leftpage); + lopaque = BTPageGetOpaque(leftpage); /* * leftpage won't be the root when we're done. Also, clear the SPLIT_END @@ -1716,7 +1716,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, rightpage = BufferGetPage(rbuf); rightpagenumber = BufferGetBlockNumber(rbuf); /* rightpage was initialized by _bt_getbuf */ - ropaque = (BTPageOpaque) PageGetSpecialPointer(rightpage); + ropaque = BTPageGetOpaque(rightpage); /* * Finish off remaining leftpage special area fields. They cannot be set @@ -1887,7 +1887,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, { sbuf = _bt_getbuf(rel, oopaque->btpo_next, BT_WRITE); spage = BufferGetPage(sbuf); - sopaque = (BTPageOpaque) PageGetSpecialPointer(spage); + sopaque = BTPageGetOpaque(spage); if (sopaque->btpo_prev != origpagenumber) { memset(rightpage, 0, BufferGetPageSize(rbuf)); @@ -1952,7 +1952,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, if (!isleaf) { Page cpage = BufferGetPage(cbuf); - BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage); + BTPageOpaque cpageop = BTPageGetOpaque(cpage); cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; MarkBufferDirty(cbuf); @@ -2139,7 +2139,7 @@ _bt_insert_parent(Relation rel, BTPageOpaque opaque; elog(DEBUG2, "concurrent ROOT page split"); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * We should never reach here when a leaf page split takes place @@ -2230,7 +2230,7 @@ void _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack) { Page lpage = BufferGetPage(lbuf); - BTPageOpaque lpageop = (BTPageOpaque) PageGetSpecialPointer(lpage); + BTPageOpaque lpageop = BTPageGetOpaque(lpage); Buffer rbuf; Page rpage; BTPageOpaque rpageop; @@ -2242,7 +2242,7 @@ _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack) /* Lock right sibling, the one missing the downlink */ rbuf = _bt_getbuf(rel, lpageop->btpo_next, BT_WRITE); rpage = BufferGetPage(rbuf); - rpageop = (BTPageOpaque) PageGetSpecialPointer(rpage); + rpageop = BTPageGetOpaque(rpage); /* Could this be a root split? */ if (!stack) @@ -2320,7 +2320,7 @@ _bt_getstackbuf(Relation rel, BTStack stack, BlockNumber child) buf = _bt_getbuf(rel, blkno, BT_WRITE); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_INCOMPLETE_SPLIT(opaque)) { @@ -2451,7 +2451,7 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf) lbkno = BufferGetBlockNumber(lbuf); rbkno = BufferGetBlockNumber(rbuf); lpage = BufferGetPage(lbuf); - lopaque = (BTPageOpaque) PageGetSpecialPointer(lpage); + lopaque = BTPageGetOpaque(lpage); /* get a new root page */ rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE); @@ -2492,11 +2492,11 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf) _bt_upgrademetapage(metapg); /* set btree special data */ - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE; rootopaque->btpo_flags = BTP_ROOT; rootopaque->btpo_level = - ((BTPageOpaque) PageGetSpecialPointer(lpage))->btpo_level + 1; + (BTPageGetOpaque(lpage))->btpo_level + 1; rootopaque->btpo_cycleid = 0; /* update metapage data */ @@ -2680,7 +2680,7 @@ _bt_delete_or_dedup_one_page(Relation rel, Relation heapRel, Buffer buffer = insertstate->buf; BTScanInsert itup_key = insertstate->itup_key; Page page = BufferGetPage(buffer); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); Assert(simpleonly || itup_key->heapkeyspace); diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c index 6b5f01e1d0..20adb602a4 100644 --- a/src/backend/access/nbtree/nbtpage.c +++ b/src/backend/access/nbtree/nbtpage.c @@ -85,7 +85,7 @@ _bt_initmetapage(Page page, BlockNumber rootbknum, uint32 level, metad->btm_last_cleanup_num_heap_tuples = -1.0; metad->btm_allequalimage = allequalimage; - metaopaque = (BTPageOpaque) PageGetSpecialPointer(page); + metaopaque = BTPageGetOpaque(page); metaopaque->btpo_flags = BTP_META; /* @@ -112,7 +112,7 @@ _bt_upgrademetapage(Page page) BTPageOpaque metaopaque PG_USED_FOR_ASSERTS_ONLY; metad = BTPageGetMeta(page); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(page); + metaopaque = BTPageGetOpaque(page); /* It must be really a meta page of upgradable version */ Assert(metaopaque->btpo_flags & BTP_META); @@ -148,7 +148,7 @@ _bt_getmeta(Relation rel, Buffer metabuf) BTMetaPageData *metad; metapg = BufferGetPage(metabuf); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg); + metaopaque = BTPageGetOpaque(metapg); metad = BTPageGetMeta(metapg); /* sanity-check the metapage */ @@ -372,7 +372,7 @@ _bt_getroot(Relation rel, int access) rootbuf = _bt_getbuf(rel, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); /* * Since the cache might be stale, we check the page more carefully @@ -440,7 +440,7 @@ _bt_getroot(Relation rel, int access) rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE); rootblkno = BufferGetBlockNumber(rootbuf); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE; rootopaque->btpo_flags = (BTP_LEAF | BTP_ROOT); rootopaque->btpo_level = 0; @@ -534,7 +534,7 @@ _bt_getroot(Relation rel, int access) { rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); if (!P_IGNORE(rootopaque)) break; @@ -598,7 +598,7 @@ _bt_gettrueroot(Relation rel) metabuf = _bt_getbuf(rel, BTREE_METAPAGE, BT_READ); metapg = BufferGetPage(metabuf); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg); + metaopaque = BTPageGetOpaque(metapg); metad = BTPageGetMeta(metapg); if (!P_ISMETA(metaopaque) || @@ -637,7 +637,7 @@ _bt_gettrueroot(Relation rel) { rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); if (!P_IGNORE(rootopaque)) break; @@ -1220,7 +1220,7 @@ _bt_delitems_vacuum(Relation rel, Buffer buf, * We can clear the vacuum cycle ID since this page has certainly been * processed by the current vacuum scan. */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_cycleid = 0; /* @@ -1338,7 +1338,7 @@ _bt_delitems_delete(Relation rel, Buffer buf, TransactionId latestRemovedXid, * Unlike _bt_delitems_vacuum, we *must not* clear the vacuum cycle ID at * this point. The VACUUM command alone controls vacuum cycle IDs. */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Clear the BTP_HAS_GARBAGE page flag. @@ -1718,7 +1718,7 @@ _bt_leftsib_splitflag(Relation rel, BlockNumber leftsib, BlockNumber target) buf = _bt_getbuf(rel, leftsib, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If the left sibling was concurrently split, so that its next-pointer @@ -1773,7 +1773,7 @@ _bt_rightsib_halfdeadflag(Relation rel, BlockNumber leafrightsib) buf = _bt_getbuf(rel, leafrightsib, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque)); result = P_ISHALFDEAD(opaque); @@ -1842,7 +1842,7 @@ _bt_pagedel(Relation rel, Buffer leafbuf, BTVacState *vstate) for (;;) { page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Internal pages are never deleted directly, only as part of deleting @@ -2099,7 +2099,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) IndexTupleData trunctuple; page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(!P_RIGHTMOST(opaque) && !P_ISROOT(opaque) && P_ISLEAF(opaque) && !P_IGNORE(opaque) && @@ -2154,7 +2154,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * before entering the critical section --- otherwise it'd be a PANIC. */ page = BufferGetPage(subtreeparent); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); #ifdef USE_ASSERT_CHECKING @@ -2201,7 +2201,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * nbtree/README. */ page = BufferGetPage(subtreeparent); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); itemid = PageGetItemId(page, poffset); itup = (IndexTuple) PageGetItem(page, itemid); @@ -2216,7 +2216,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * is set to InvalidBlockNumber. */ page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags |= BTP_HALF_DEAD; Assert(PageGetMaxOffsetNumber(page) == P_HIKEY); @@ -2253,7 +2253,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) XLogRegisterBuffer(1, subtreeparent, REGBUF_STANDARD); page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); xlrec.leftblk = opaque->btpo_prev; xlrec.rightblk = opaque->btpo_next; @@ -2325,7 +2325,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, BlockNumber leaftopparent; page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque) && P_ISHALFDEAD(opaque)); @@ -2364,7 +2364,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* Fetch the block number of the target's left sibling */ buf = _bt_getbuf(rel, target, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); leftsib = opaque->btpo_prev; targetlevel = opaque->btpo_level; Assert(targetlevel > 0); @@ -2391,7 +2391,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, { lbuf = _bt_getbuf(rel, leftsib, BT_WRITE); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); while (P_ISDELETED(opaque) || opaque->btpo_next != target) { bool leftsibvalid = true; @@ -2441,7 +2441,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* step right one page */ lbuf = _bt_getbuf(rel, leftsib, BT_WRITE); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } } else @@ -2450,7 +2450,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* Next write-lock the target page itself */ _bt_lockbuf(rel, buf, BT_WRITE); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Check page is still empty etc, else abandon deletion. This is just for @@ -2505,7 +2505,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, rightsib = opaque->btpo_next; rbuf = _bt_getbuf(rel, rightsib, BT_WRITE); page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (opaque->btpo_prev != target) ereport(ERROR, (errcode(ERRCODE_INDEX_CORRUPTED), @@ -2528,7 +2528,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, if (leftsib == P_NONE && rightsib_is_rightmost) { page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_RIGHTMOST(opaque)) { /* rightsib will be the only one left on the level */ @@ -2565,12 +2565,12 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, if (BufferIsValid(lbuf)) { page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(opaque->btpo_next == target); opaque->btpo_next = rightsib; } page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(opaque->btpo_prev == target); opaque->btpo_prev = leftsib; @@ -2599,7 +2599,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, * of that scan. */ page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISHALFDEAD(opaque) || !P_ISLEAF(opaque)); /* @@ -2814,7 +2814,7 @@ _bt_lock_subtree_parent(Relation rel, BlockNumber child, BTStack stack, parentoffset = stack->bts_offset; page = BufferGetPage(pbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); leftsibparent = opaque->btpo_prev; diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c index c9b4964c1e..07600b86fb 100644 --- a/src/backend/access/nbtree/nbtree.c +++ b/src/backend/access/nbtree/nbtree.c @@ -1070,7 +1070,7 @@ backtrack: if (!PageIsNew(page)) { _bt_checkpage(rel, buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } Assert(blkno <= scanblkno); diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c index 9d82d4904d..c74543bfde 100644 --- a/src/backend/access/nbtree/nbtsearch.c +++ b/src/backend/access/nbtree/nbtsearch.c @@ -134,7 +134,7 @@ _bt_search(Relation rel, BTScanInsert key, Buffer *bufP, int access, /* if this is a leaf page, we're done */ page = BufferGetPage(*bufP); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISLEAF(opaque)) break; @@ -268,7 +268,7 @@ _bt_moveright(Relation rel, { page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_RIGHTMOST(opaque)) break; @@ -347,7 +347,7 @@ _bt_binsrch(Relation rel, cmpval; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Requesting nextkey semantics while using scantid seems nonsensical */ Assert(!key->nextkey || key->scantid == NULL); @@ -451,7 +451,7 @@ _bt_binsrch_insert(Relation rel, BTInsertState insertstate) cmpval; page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); Assert(!key->nextkey); @@ -659,7 +659,7 @@ _bt_compare(Relation rel, OffsetNumber offnum) { TupleDesc itupdesc = RelationGetDescr(rel); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); IndexTuple itup; ItemPointer heapTid; ScanKey scankey; @@ -1536,7 +1536,7 @@ _bt_readpage(IndexScanDesc scan, ScanDirection dir, OffsetNumber offnum) Assert(BufferIsValid(so->currPos.buf)); page = BufferGetPage(so->currPos.buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* allow next page be processed by parallel worker */ if (scan->parallel_scan) @@ -2007,7 +2007,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir) so->currPos.buf = _bt_getbuf(rel, blkno, BT_READ); page = BufferGetPage(so->currPos.buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* check for deleted page */ if (!P_IGNORE(opaque)) { @@ -2110,7 +2110,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir) */ page = BufferGetPage(so->currPos.buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_IGNORE(opaque)) { PredicateLockPage(rel, BufferGetBlockNumber(so->currPos.buf), scan->xs_snapshot); @@ -2191,7 +2191,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) BTPageOpaque opaque; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); for (;;) { @@ -2216,7 +2216,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_getbuf(rel, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If this isn't the page we want, walk right till we find what we @@ -2243,14 +2243,14 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } /* Return to the original page to see what's up */ buf = _bt_relandgetbuf(rel, buf, obknum, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* @@ -2268,7 +2268,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_ISDELETED(opaque)) break; } @@ -2329,7 +2329,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); for (;;) { @@ -2349,7 +2349,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } /* Done? */ @@ -2372,7 +2372,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } return buf; @@ -2418,7 +2418,7 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); if (ScanDirectionIsForward(dir)) diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index 8a19de2f66..c074513efa 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -625,7 +625,7 @@ _bt_blnewpage(uint32 level) _bt_pageinit(page, BLCKSZ); /* Initialize BT opaque state */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_prev = opaque->btpo_next = P_NONE; opaque->btpo_level = level; opaque->btpo_flags = (level > 0) ? 0 : BTP_LEAF; @@ -1000,9 +1000,9 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup, Assert((BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) <= IndexRelationGetNumberOfKeyAttributes(wstate->index) && BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) > 0) || - P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage))); + P_LEFTMOST(BTPageGetOpaque(opage))); Assert(BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) == 0 || - !P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage))); + !P_LEFTMOST(BTPageGetOpaque(opage))); BTreeTupleSetDownLink(state->btps_lowkey, oblkno); _bt_buildadd(wstate, state->btps_next, state->btps_lowkey, 0); pfree(state->btps_lowkey); @@ -1017,8 +1017,8 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup, * Set the sibling links for both pages. */ { - BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(opage); - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(npage); + BTPageOpaque oopaque = BTPageGetOpaque(opage); + BTPageOpaque nopaque = BTPageGetOpaque(npage); oopaque->btpo_next = nblkno; nopaque->btpo_prev = oblkno; @@ -1125,7 +1125,7 @@ _bt_uppershutdown(BTWriteState *wstate, BTPageState *state) BTPageOpaque opaque; blkno = s->btps_blkno; - opaque = (BTPageOpaque) PageGetSpecialPointer(s->btps_page); + opaque = BTPageGetOpaque(s->btps_page); /* * We have to link the last page on this level to somewhere. diff --git a/src/backend/access/nbtree/nbtsplitloc.c b/src/backend/access/nbtree/nbtsplitloc.c index c46594e1a2..ee01ceafda 100644 --- a/src/backend/access/nbtree/nbtsplitloc.c +++ b/src/backend/access/nbtree/nbtsplitloc.c @@ -152,7 +152,7 @@ _bt_findsplitloc(Relation rel, SplitPoint leftpage, rightpage; - opaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + opaque = BTPageGetOpaque(origpage); maxoff = PageGetMaxOffsetNumber(origpage); /* Total free space available on a btree page, after fixed overhead */ diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c index 84164748b3..96c72fc432 100644 --- a/src/backend/access/nbtree/nbtutils.c +++ b/src/backend/access/nbtree/nbtutils.c @@ -1774,7 +1774,7 @@ _bt_killitems(IndexScanDesc scan) } } - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); minoff = P_FIRSTDATAKEY(opaque); maxoff = PageGetMaxOffsetNumber(page); @@ -2474,7 +2474,7 @@ _bt_check_natts(Relation rel, bool heapkeyspace, Page page, OffsetNumber offnum) { int16 natts = IndexRelationGetNumberOfAttributes(rel); int16 nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); IndexTuple itup; int tupnatts; @@ -2662,7 +2662,7 @@ _bt_check_third_page(Relation rel, Relation heap, bool needheaptidspace, * Internal page insertions cannot fail here, because that would mean that * an earlier leaf level insertion that should have failed didn't */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_ISLEAF(opaque)) elog(ERROR, "cannot insert oversized tuple of size %zu on internal page of index \"%s\"", itemsz, RelationGetRelationName(rel)); diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c index 611f412ba8..fba124b940 100644 --- a/src/backend/access/nbtree/nbtxlog.c +++ b/src/backend/access/nbtree/nbtxlog.c @@ -115,7 +115,7 @@ _bt_restore_meta(XLogReaderState *record, uint8 block_id) md->btm_last_cleanup_num_heap_tuples = -1.0; md->btm_allequalimage = xlrec->allequalimage; - pageop = (BTPageOpaque) PageGetSpecialPointer(metapg); + pageop = BTPageGetOpaque(metapg); pageop->btpo_flags = BTP_META; /* @@ -146,7 +146,7 @@ _bt_clear_incomplete_split(XLogReaderState *record, uint8 block_id) if (XLogReadBufferForRedo(record, block_id, &buf) == BLK_NEEDS_REDO) { Page page = (Page) BufferGetPage(buf); - BTPageOpaque pageop = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque pageop = BTPageGetOpaque(page); Assert(P_INCOMPLETE_SPLIT(pageop)); pageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; @@ -292,7 +292,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) rpage = (Page) BufferGetPage(rbuf); _bt_pageinit(rpage, BufferGetPageSize(rbuf)); - ropaque = (BTPageOpaque) PageGetSpecialPointer(rpage); + ropaque = BTPageGetOpaque(rpage); ropaque->btpo_prev = origpagenumber; ropaque->btpo_next = spagenumber; @@ -317,7 +317,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) * same for the right page. */ Page origpage = (Page) BufferGetPage(buf); - BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + BTPageOpaque oopaque = BTPageGetOpaque(origpage); OffsetNumber off; IndexTuple newitem = NULL, left_hikey = NULL, @@ -442,7 +442,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) if (XLogReadBufferForRedo(record, 2, &sbuf) == BLK_NEEDS_REDO) { Page spage = (Page) BufferGetPage(sbuf); - BTPageOpaque spageop = (BTPageOpaque) PageGetSpecialPointer(spage); + BTPageOpaque spageop = BTPageGetOpaque(spage); spageop->btpo_prev = rightpagenumber; @@ -473,7 +473,7 @@ btree_xlog_dedup(XLogReaderState *record) { char *ptr = XLogRecGetBlockData(record, 0, NULL); Page page = (Page) BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); OffsetNumber offnum, minoff, maxoff; @@ -541,7 +541,7 @@ btree_xlog_dedup(XLogReaderState *record) if (P_HAS_GARBAGE(opaque)) { - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage); + BTPageOpaque nopaque = BTPageGetOpaque(newpage); nopaque->btpo_flags &= ~BTP_HAS_GARBAGE; } @@ -639,7 +639,7 @@ btree_xlog_vacuum(XLogReaderState *record) * Mark the page as not containing any LP_DEAD items --- see comments * in _bt_delitems_vacuum(). */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags &= ~BTP_HAS_GARBAGE; PageSetLSN(page, lsn); @@ -699,7 +699,7 @@ btree_xlog_delete(XLogReaderState *record) PageIndexMultiDelete(page, (OffsetNumber *) ptr, xlrec->ndeleted); /* Mark the page as not containing any LP_DEAD items */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags &= ~BTP_HAS_GARBAGE; PageSetLSN(page, lsn); @@ -737,7 +737,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record) BlockNumber rightsib; page = (Page) BufferGetPage(buffer); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); poffset = xlrec->poffset; @@ -768,7 +768,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(buffer); _bt_pageinit(page, BufferGetPageSize(buffer)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = xlrec->leftblk; pageop->btpo_next = xlrec->rightblk; @@ -833,7 +833,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) if (XLogReadBufferForRedo(record, 1, &leftbuf) == BLK_NEEDS_REDO) { page = (Page) BufferGetPage(leftbuf); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_next = rightsib; PageSetLSN(page, lsn); @@ -848,7 +848,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(target); _bt_pageinit(page, BufferGetPageSize(target)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = leftsib; pageop->btpo_next = rightsib; @@ -865,7 +865,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) if (XLogReadBufferForRedo(record, 2, &rightbuf) == BLK_NEEDS_REDO) { page = (Page) BufferGetPage(rightbuf); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = leftsib; PageSetLSN(page, lsn); @@ -906,7 +906,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(leafbuf); _bt_pageinit(page, BufferGetPageSize(leafbuf)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_flags = BTP_HALF_DEAD | BTP_LEAF; pageop->btpo_prev = xlrec->leafleftsib; @@ -948,7 +948,7 @@ btree_xlog_newroot(XLogReaderState *record) page = (Page) BufferGetPage(buffer); _bt_pageinit(page, BufferGetPageSize(buffer)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_flags = BTP_ROOT; pageop->btpo_prev = pageop->btpo_next = P_NONE; @@ -1097,7 +1097,7 @@ btree_mask(char *pagedata, BlockNumber blkno) mask_page_hint_bits(page); mask_unused_space(page); - maskopaq = (BTPageOpaque) PageGetSpecialPointer(page); + maskopaq = BTPageGetOpaque(page); if (P_ISLEAF(maskopaq)) { diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h index 9fec6fb1a8..31edddefc0 100644 --- a/src/include/access/nbtree.h +++ b/src/include/access/nbtree.h @@ -70,6 +70,13 @@ typedef struct BTPageOpaqueData typedef BTPageOpaqueData *BTPageOpaque; +/* + * Pre-aligned accessor to the opaque data in the page's special region. + * Avoids data dependency on page header in non-assert builds. + */ +#define BTPageGetOpaque(page) \ + ((BTPageOpaque) PageGetSpecialOpaque((page), BTPageOpaqueData)) + /* Bits defined in btpo_flags */ #define BTP_LEAF (1 << 0) /* leaf page, i.e. not internal page */ #define BTP_ROOT (1 << 1) /* root page (has no parent) */ @@ -241,7 +248,7 @@ BTPageSetDeleted(Page page, FullTransactionId safexid) PageHeader header; BTDeletedPageData *contents; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); header = ((PageHeader) page); opaque->btpo_flags &= ~BTP_HALF_DEAD; @@ -263,7 +270,7 @@ BTPageGetDeleteXid(Page page) /* We only expect to be called with a deleted page */ Assert(!PageIsNew(page)); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISDELETED(opaque)); /* pg_upgrade'd deleted page -- must be safe to delete now */ @@ -294,7 +301,7 @@ BTPageIsRecyclable(Page page) Assert(!PageIsNew(page)); /* Recycling okay iff page is deleted and safexid is old enough */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* -- 2.30.2 ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-03-28 04:31 Michael Paquier <[email protected]> parent: Matthias van de Meent <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Michael Paquier @ 2022-03-28 04:31 UTC (permalink / raw) To: Matthias van de Meent <[email protected]>; +Cc: pgsql-hackers On Wed, Feb 16, 2022 at 10:24:58PM +0100, Matthias van de Meent wrote: > A first good reason to do this is preventing further damage when a > page is corrupted: if I can somehow overwrite pd_special, > non-assert-enabled builds would start reading and writing at arbitrary > offsets from the page pointer, quite possibly in subsequent buffers > (or worse, on the stack, in case of stack-allocated blocks). Well, pageinspect has proved to be rather careless in this area for a couple of years, but this just came from the fact that we called PageGetSpecialPointer() before checking that PageGetSpecialSize() maps with the MAXALIGN'd size of the opaque area, if the related AM has one. I am not sure that we need to worry about corruptions, as data checksums would offer protection for most cases users usually need to worry about, at the exception of page corruptions because of memory for pages already read in the PG shared buffers from disk or even the OS cache. > A second reason would be less indirection to get to the opaque > pointer. This should improve performance a bit in those cases where we > (initially) only want to access the [Index]PageOpaque struct. We don't have many cases that do that, do we? > Lastly, 0002 and 0003 remove some repetitive tasks of dealing with the > [nbtree, hash] opaques by providing a typed accessor macro similar to > what is used in the GIN and (SP-)GIST index methods; improving the > legibility of the code and decreasing the churn. +#define PageGetSpecialOpaque(page, OpaqueDataTyp) \ +( \ + AssertMacro(PageGetPageSize(page) == BLCKSZ && \ + PageGetSpecialSize(page) == MAXALIGN(sizeof(OpaqueDataTyp))), \ + (OpaqueDataTyp *) ((char *) (page) + (BLCKSZ - MAXALIGN(sizeof(OpaqueDataTyp)))) \ +) Did you notice PageValidateSpecialPointer() that mentions MSVC? Could this stuff a problem if not an inline function. Perhaps you should do a s/OpaqueDataTyp/OpaqueDataType/. As a whole, this patch set looks like an improvement in terms of checks and consistency regarding the special area handling across the different AMs for the backend code, while reducing the MAXALIGN-ism on all those sizes, and this tends to be missed. Any other opinions? -- Michael Attachments: [application/pgp-signature] signature.asc (833B, ../../[email protected]/2-signature.asc) download ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-03-28 15:09 Matthias van de Meent <[email protected]> parent: Michael Paquier <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Matthias van de Meent @ 2022-03-28 15:09 UTC (permalink / raw) To: Michael Paquier <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; pgsql-hackers On Mon, 28 Mar 2022 at 06:33, Michael Paquier <[email protected]> wrote: > > On Wed, Feb 16, 2022 at 10:24:58PM +0100, Matthias van de Meent wrote: > > A first good reason to do this is preventing further damage when a > > page is corrupted: if I can somehow overwrite pd_special, > > non-assert-enabled builds would start reading and writing at arbitrary > > offsets from the page pointer, quite possibly in subsequent buffers > > (or worse, on the stack, in case of stack-allocated blocks). > > Well, pageinspect has proved to be rather careless in this area for a > couple of years, but this just came from the fact that we called > PageGetSpecialPointer() before checking that PageGetSpecialSize() maps > with the MAXALIGN'd size of the opaque area, if the related AM has > one. > > I am not sure that we need to worry about corruptions, as data > checksums would offer protection for most cases users usually need to > worry about, at the exception of page corruptions because of memory > for pages already read in the PG shared buffers from disk or even the > OS cache. Not all clusters have checksums enabled (boo!, but we can't realistically fix that), so on-disk corruption could reasonably propagate to the rest of such system. Additionally, checksums are only checked on read, and updated when the page is written to disk (in PageSetChecksumCopy called from FlushBuffer), but this does not check for signs of page corruption. As such, a memory bug resulting in in-memory corruption of pd_special would persist and would currently have the potential to further corrupt neighbouring buffers. > > A second reason would be less indirection to get to the opaque > > pointer. This should improve performance a bit in those cases where we > > (initially) only want to access the [Index]PageOpaque struct. > > We don't have many cases that do that, do we? Indeed not many, but I know that at least the nbtree-code has some cases where it uses the opaque before other fields in the header are accessed (sometimes even without accessing the header for other reasons): in _bt_moveright and _bt_walk_left. There might be more; but these are cases I know of. > > Lastly, 0002 and 0003 remove some repetitive tasks of dealing with the > > [nbtree, hash] opaques by providing a typed accessor macro similar to > > what is used in the GIN and (SP-)GIST index methods; improving the > > legibility of the code and decreasing the churn. > > +#define PageGetSpecialOpaque(page, OpaqueDataTyp) \ > +( \ > + AssertMacro(PageGetPageSize(page) == BLCKSZ && \ > + PageGetSpecialSize(page) == MAXALIGN(sizeof(OpaqueDataTyp))), \ > + (OpaqueDataTyp *) ((char *) (page) + (BLCKSZ - MAXALIGN(sizeof(OpaqueDataTyp)))) \ > +) > > Did you notice PageValidateSpecialPointer() that mentions MSVC? Could > this stuff a problem if not an inline function. I'm not sure; but the CFbot build (using whatever MSVC is used with latest Window Server 2019, VS 19) failed to complain in this case. Furthermore, the case mentioned in the comment of PageValidateSpecialPointer() refers to problems that only happened after the macro was updated from one MacroAssert to three seperate MacroAssert()s; this new code currently only has one, so we should be fine for now. > Perhaps you should do a s/OpaqueDataTyp/OpaqueDataType/. This has been fixed in attached v2; and apart from tweaks in the commit messages there have been no other changes. > As a whole, this patch set looks like an improvement in terms of > checks and consistency regarding the special area handling across the > different AMs for the backend code, while reducing the MAXALIGN-ism on > all those sizes, and this tends to be missed. Thanks! -Matthias Attachments: [application/x-patch] v2-0001-Add-known-size-pre-aligned-special-area-pointer-m.patch (4.0K, ../../CAEze2Wjjx4REsge5kxNjDjKDVvkqbruqxVLykxj_UufZ0xzbOw@mail.gmail.com/2-v2-0001-Add-known-size-pre-aligned-special-area-pointer-m.patch) download | inline diff: From c22128e0e63ab83f9009a1466ea50c46878d7650 Mon Sep 17 00:00:00 2001 From: Matthias van de Meent <[email protected]> Date: Mon, 28 Mar 2022 14:53:43 +0200 Subject: [PATCH v2 1/3] Add known-size pre-aligned special area pointer macro This removes 1 layer of indirection for special areas of which we know the type (=size) and location. Special area access through the page header is an extra cache line that needs to be fetched. If might only want to look at the special area, it is much less effort to calculate the offset to the special area directly instead of first checking the page header - saving one cache line to fetch. Assertions are added to check that the page has a correctly sized special area, and that the page is of the expected size. This detects data corruption, instead of doing random reads/writes into the page or data allocated next to the page being accessed. Additionally, updates the GIN, GIST and SP-GIST [Index]PageGetOpaque macros with the new pre-aligned special area accessor. --- src/include/access/ginblock.h | 3 ++- src/include/access/gist.h | 3 ++- src/include/access/spgist_private.h | 3 ++- src/include/storage/bufpage.h | 14 ++++++++++++++ 4 files changed, 20 insertions(+), 3 deletions(-) diff --git a/src/include/access/ginblock.h b/src/include/access/ginblock.h index 9347f464f3..3680098c98 100644 --- a/src/include/access/ginblock.h +++ b/src/include/access/ginblock.h @@ -108,7 +108,8 @@ typedef struct GinMetaPageData /* * Macros for accessing a GIN index page's opaque data */ -#define GinPageGetOpaque(page) ( (GinPageOpaque) PageGetSpecialPointer(page) ) +#define GinPageGetOpaque(page) \ + ((GinPageOpaque) PageGetSpecialOpaque(page, GinPageOpaqueData)) #define GinPageIsLeaf(page) ( (GinPageGetOpaque(page)->flags & GIN_LEAF) != 0 ) #define GinPageSetLeaf(page) ( GinPageGetOpaque(page)->flags |= GIN_LEAF ) diff --git a/src/include/access/gist.h b/src/include/access/gist.h index a3337627b8..51223e9051 100644 --- a/src/include/access/gist.h +++ b/src/include/access/gist.h @@ -164,7 +164,8 @@ typedef struct GISTENTRY bool leafkey; } GISTENTRY; -#define GistPageGetOpaque(page) ( (GISTPageOpaque) PageGetSpecialPointer(page) ) +#define GistPageGetOpaque(page) \ + ((GISTPageOpaque) PageGetSpecialOpaque(page, GISTPageOpaqueData)) #define GistPageIsLeaf(page) ( GistPageGetOpaque(page)->flags & F_LEAF) #define GIST_LEAF(entry) (GistPageIsLeaf((entry)->page)) diff --git a/src/include/access/spgist_private.h b/src/include/access/spgist_private.h index eb56b1c6b8..b0bdc7df3e 100644 --- a/src/include/access/spgist_private.h +++ b/src/include/access/spgist_private.h @@ -75,7 +75,8 @@ typedef SpGistPageOpaqueData *SpGistPageOpaque; #define SPGIST_LEAF (1<<2) #define SPGIST_NULLS (1<<3) -#define SpGistPageGetOpaque(page) ((SpGistPageOpaque) PageGetSpecialPointer(page)) +#define SpGistPageGetOpaque(page) \ + ((SpGistPageOpaque) PageGetSpecialOpaque(page, SpGistPageOpaqueData)) #define SpGistPageIsMeta(page) (SpGistPageGetOpaque(page)->flags & SPGIST_META) #define SpGistPageIsDeleted(page) (SpGistPageGetOpaque(page)->flags & SPGIST_DELETED) #define SpGistPageIsLeaf(page) (SpGistPageGetOpaque(page)->flags & SPGIST_LEAF) diff --git a/src/include/storage/bufpage.h b/src/include/storage/bufpage.h index e9f253f2c8..e96595f338 100644 --- a/src/include/storage/bufpage.h +++ b/src/include/storage/bufpage.h @@ -329,6 +329,20 @@ PageValidateSpecialPointer(Page page) (char *) ((char *) (page) + ((PageHeader) (page))->pd_special) \ ) +/* + * PageGetSpecialOpaque + * Returns pointer to special space on a page, of the given type. + * This removes the data dependency on the page header in builds + * without asserts enabled. + */ +#define PageGetSpecialOpaque(page, OpaqueDataType) \ +( \ + AssertMacro(PageGetPageSize(page) == BLCKSZ && \ + PageGetSpecialSize(page) == MAXALIGN(sizeof(OpaqueDataType))), \ + (OpaqueDataType *) ((char *) (page) + \ + (BLCKSZ - MAXALIGN(sizeof(OpaqueDataType)))) \ +) + /* * PageGetItem * Retrieves an item on the given page. -- 2.30.2 [application/x-patch] v2-0002-Update-nbtree-code-to-use-PageGetSpecialOpaque-re.patch (44.7K, ../../CAEze2Wjjx4REsge5kxNjDjKDVvkqbruqxVLykxj_UufZ0xzbOw@mail.gmail.com/3-v2-0002-Update-nbtree-code-to-use-PageGetSpecialOpaque-re.patch) download | inline diff: From 48db6037b088bf21dc2fd11b13d1d565c8fd9789 Mon Sep 17 00:00:00 2001 From: Matthias van de Meent <[email protected]> Date: Mon, 28 Mar 2022 16:44:57 +0200 Subject: [PATCH v2 2/3] Update nbtree code to use PageGetSpecialOpaque; replacing PageGetSpecialPointer+cast As in the earlier patch, this reduces memory access requirements by directly reading into the target space instead of needing to access the header of the page first. Also makes the code a lot more readable by replacing templated macro+casts with a single macro specialized for BTree page opaques. --- contrib/amcheck/verify_nbtree.c | 32 +++++++------- contrib/pageinspect/btreefuncs.c | 6 +-- contrib/pgstattuple/pgstatindex.c | 2 +- contrib/pgstattuple/pgstattuple.c | 2 +- src/backend/access/nbtree/nbtdedup.c | 6 +-- src/backend/access/nbtree/nbtinsert.c | 46 ++++++++++---------- src/backend/access/nbtree/nbtpage.c | 58 ++++++++++++------------- src/backend/access/nbtree/nbtree.c | 2 +- src/backend/access/nbtree/nbtsearch.c | 34 +++++++-------- src/backend/access/nbtree/nbtsort.c | 12 ++--- src/backend/access/nbtree/nbtsplitloc.c | 2 +- src/backend/access/nbtree/nbtutils.c | 6 +-- src/backend/access/nbtree/nbtxlog.c | 34 +++++++-------- src/include/access/nbtree.h | 13 ++++-- 14 files changed, 131 insertions(+), 124 deletions(-) diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c index d2510ee648..70278c4f93 100644 --- a/contrib/amcheck/verify_nbtree.c +++ b/contrib/amcheck/verify_nbtree.c @@ -691,7 +691,7 @@ bt_check_level_from_leftmost(BtreeCheckState *state, BtreeLevel level) state->target = palloc_btree_page(state, state->targetblock); state->targetlsn = PageGetLSN(state->target); - opaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + opaque = BTPageGetOpaque(state->target); if (P_IGNORE(opaque)) { @@ -927,7 +927,7 @@ bt_recheck_sibling_links(BtreeCheckState *state, LockBuffer(lbuf, BT_READ); _bt_checkpage(state->rel, lbuf); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* @@ -951,7 +951,7 @@ bt_recheck_sibling_links(BtreeCheckState *state, LockBuffer(newtargetbuf, BT_READ); _bt_checkpage(state->rel, newtargetbuf); page = BufferGetPage(newtargetbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* btpo_prev_from_target may have changed; update it */ btpo_prev_from_target = opaque->btpo_prev; } @@ -1049,7 +1049,7 @@ bt_target_page_check(BtreeCheckState *state) OffsetNumber max; BTPageOpaque topaque; - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); max = PageGetMaxOffsetNumber(state->target); elog(DEBUG2, "verifying %u items on %s block %u", max, @@ -1478,7 +1478,7 @@ bt_target_page_check(BtreeCheckState *state) /* Get fresh copy of target page */ state->target = palloc_btree_page(state, state->targetblock); /* Note that we deliberately do not update target LSN */ - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); /* * All !readonly checks now performed; just return @@ -1552,7 +1552,7 @@ bt_right_page_check_scankey(BtreeCheckState *state) OffsetNumber nline; /* Determine target's next block number */ - opaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + opaque = BTPageGetOpaque(state->target); /* If target is already rightmost, no right sibling; nothing to do here */ if (P_RIGHTMOST(opaque)) @@ -1588,7 +1588,7 @@ bt_right_page_check_scankey(BtreeCheckState *state) CHECK_FOR_INTERRUPTS(); rightpage = palloc_btree_page(state, targetnext); - opaque = (BTPageOpaque) PageGetSpecialPointer(rightpage); + opaque = BTPageGetOpaque(rightpage); if (!P_IGNORE(opaque) || P_RIGHTMOST(opaque)) break; @@ -1893,7 +1893,7 @@ bt_child_highkey_check(BtreeCheckState *state, else page = palloc_btree_page(state, blkno); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* The first page we visit at the level should be leftmost */ if (first && !BlockNumberIsValid(state->prevrightlink) && !P_LEFTMOST(opaque)) @@ -1971,7 +1971,7 @@ bt_child_highkey_check(BtreeCheckState *state, else pivotkey_offset = target_downlinkoffnum; - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); if (!offset_is_negative_infinity(topaque, pivotkey_offset)) { @@ -2128,9 +2128,9 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey, * Check all items, rather than checking just the first and trusting that * the operator class obeys the transitive law. */ - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); child = palloc_btree_page(state, childblock); - copaque = (BTPageOpaque) PageGetSpecialPointer(child); + copaque = BTPageGetOpaque(child); maxoffset = PageGetMaxOffsetNumber(child); /* @@ -2235,7 +2235,7 @@ static void bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit, BlockNumber blkno, Page page) { - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); ItemId itemid; IndexTuple itup; Page child; @@ -2319,7 +2319,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit, CHECK_FOR_INTERRUPTS(); child = palloc_btree_page(state, childblk); - copaque = (BTPageOpaque) PageGetSpecialPointer(child); + copaque = BTPageGetOpaque(child); if (P_ISLEAF(copaque)) break; @@ -2780,7 +2780,7 @@ invariant_l_offset(BtreeCheckState *state, BTScanInsert key, bool nonpivot; ritup = (IndexTuple) PageGetItem(state->target, itemid); - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); nonpivot = P_ISLEAF(topaque) && upperbound >= P_FIRSTDATAKEY(topaque); /* Get number of keys + heap TID for item to the right */ @@ -2895,7 +2895,7 @@ invariant_l_nontarget_offset(BtreeCheckState *state, BTScanInsert key, bool nonpivot; child = (IndexTuple) PageGetItem(nontarget, itemid); - copaque = (BTPageOpaque) PageGetSpecialPointer(nontarget); + copaque = BTPageGetOpaque(nontarget); nonpivot = P_ISLEAF(copaque) && upperbound >= P_FIRSTDATAKEY(copaque); /* Get number of keys + heap TID for child/non-target item */ @@ -2954,7 +2954,7 @@ palloc_btree_page(BtreeCheckState *state, BlockNumber blocknum) memcpy(page, BufferGetPage(buffer), BLCKSZ); UnlockReleaseBuffer(buffer); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISMETA(opaque) && blocknum != BTREE_METAPAGE) ereport(ERROR, diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c index 7651c59bbf..3daa31c84d 100644 --- a/contrib/pageinspect/btreefuncs.c +++ b/contrib/pageinspect/btreefuncs.c @@ -93,7 +93,7 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat) Page page = BufferGetPage(buffer); PageHeader phdr = (PageHeader) page; OffsetNumber maxoff = PageGetMaxOffsetNumber(page); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); int item_size = 0; int off; @@ -525,7 +525,7 @@ bt_page_items_internal(PG_FUNCTION_ARGS, enum pageinspect_version ext_version) uargs->offset = FirstOffsetNumber; - opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page); + opaque = BTPageGetOpaque(uargs->page); if (!P_ISDELETED(opaque)) fctx->max_calls = PageGetMaxOffsetNumber(uargs->page); @@ -622,7 +622,7 @@ bt_page_items_bytea(PG_FUNCTION_ARGS) (int) MAXALIGN(sizeof(BTPageOpaqueData)), (int) PageGetSpecialSize(uargs->page)))); - opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page); + opaque = BTPageGetOpaque(uargs->page); if (P_ISMETA(opaque)) ereport(ERROR, diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c index 6c4b053dd0..b9939451b4 100644 --- a/contrib/pgstattuple/pgstatindex.c +++ b/contrib/pgstattuple/pgstatindex.c @@ -281,7 +281,7 @@ pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo) LockBuffer(buffer, BUFFER_LOCK_SHARE); page = BufferGetPage(buffer); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Determine page type, and update totals. diff --git a/contrib/pgstattuple/pgstattuple.c b/contrib/pgstattuple/pgstattuple.c index c9b8f01f9b..a9658d389b 100644 --- a/contrib/pgstattuple/pgstattuple.c +++ b/contrib/pgstattuple/pgstattuple.c @@ -415,7 +415,7 @@ pgstat_btree_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno, { BTPageOpaque opaque; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_IGNORE(opaque)) { /* deleted or half-dead page */ diff --git a/src/backend/access/nbtree/nbtdedup.c b/src/backend/access/nbtree/nbtdedup.c index 4c48554aec..3e11805293 100644 --- a/src/backend/access/nbtree/nbtdedup.c +++ b/src/backend/access/nbtree/nbtdedup.c @@ -62,7 +62,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem, minoff, maxoff; Page page = BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); Page newpage; BTDedupState state; Size pagesaving = 0; @@ -231,7 +231,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem, */ if (P_HAS_GARBAGE(opaque)) { - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage); + BTPageOpaque nopaque = BTPageGetOpaque(newpage); nopaque->btpo_flags &= ~BTP_HAS_GARBAGE; } @@ -310,7 +310,7 @@ _bt_bottomupdel_pass(Relation rel, Buffer buf, Relation heapRel, minoff, maxoff; Page page = BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); BTDedupState state; TM_IndexDeleteOp delstate; bool neverdedup; diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c index 68628ec000..f6f4af8bfe 100644 --- a/src/backend/access/nbtree/nbtinsert.c +++ b/src/backend/access/nbtree/nbtinsert.c @@ -329,7 +329,7 @@ _bt_search_insert(Relation rel, BTInsertState insertstate) _bt_checkpage(rel, insertstate->buf); page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Check if the page is still the rightmost leaf page and has @@ -428,7 +428,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel, InitDirtySnapshot(SnapshotDirty); page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); /* @@ -733,7 +733,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel, nbuf = _bt_relandgetbuf(rel, nbuf, nblkno, BT_READ); page = BufferGetPage(nbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_IGNORE(opaque)) break; if (P_RIGHTMOST(opaque)) @@ -822,7 +822,7 @@ _bt_findinsertloc(Relation rel, BTPageOpaque opaque; OffsetNumber newitemoff; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Check 1/3 of a page restriction */ if (unlikely(insertstate->itemsz > BTMaxItemSize(page))) @@ -888,7 +888,7 @@ _bt_findinsertloc(Relation rel, _bt_stepright(rel, insertstate, stack); /* Update local state after stepping right */ page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Assume duplicates (if checkingunique) */ uniquedup = true; } @@ -972,7 +972,7 @@ _bt_findinsertloc(Relation rel, _bt_stepright(rel, insertstate, stack); /* Update local state after stepping right */ page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } } @@ -1030,7 +1030,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack) BlockNumber rblkno; page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); rbuf = InvalidBuffer; rblkno = opaque->btpo_next; @@ -1038,7 +1038,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack) { rbuf = _bt_relandgetbuf(rel, rbuf, rblkno, BT_WRITE); page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If this page was incompletely split, finish the split now. We do @@ -1120,7 +1120,7 @@ _bt_insertonpg(Relation rel, IndexTuple nposting = NULL; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); isleaf = P_ISLEAF(opaque); isroot = P_ISROOT(opaque); isrightmost = P_RIGHTMOST(opaque); @@ -1296,7 +1296,7 @@ _bt_insertonpg(Relation rel, if (!isleaf) { Page cpage = BufferGetPage(cbuf); - BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage); + BTPageOpaque cpageop = BTPageGetOpaque(cpage); Assert(P_INCOMPLETE_SPLIT(cpageop)); cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; @@ -1504,7 +1504,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, * only workspace. */ origpage = BufferGetPage(buf); - oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + oopaque = BTPageGetOpaque(origpage); isleaf = P_ISLEAF(oopaque); isrightmost = P_RIGHTMOST(oopaque); maxoff = PageGetMaxOffsetNumber(origpage); @@ -1540,7 +1540,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, /* Allocate temp buffer for leftpage */ leftpage = PageGetTempPage(origpage); _bt_pageinit(leftpage, BufferGetPageSize(buf)); - lopaque = (BTPageOpaque) PageGetSpecialPointer(leftpage); + lopaque = BTPageGetOpaque(leftpage); /* * leftpage won't be the root when we're done. Also, clear the SPLIT_END @@ -1716,7 +1716,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, rightpage = BufferGetPage(rbuf); rightpagenumber = BufferGetBlockNumber(rbuf); /* rightpage was initialized by _bt_getbuf */ - ropaque = (BTPageOpaque) PageGetSpecialPointer(rightpage); + ropaque = BTPageGetOpaque(rightpage); /* * Finish off remaining leftpage special area fields. They cannot be set @@ -1887,7 +1887,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, { sbuf = _bt_getbuf(rel, oopaque->btpo_next, BT_WRITE); spage = BufferGetPage(sbuf); - sopaque = (BTPageOpaque) PageGetSpecialPointer(spage); + sopaque = BTPageGetOpaque(spage); if (sopaque->btpo_prev != origpagenumber) { memset(rightpage, 0, BufferGetPageSize(rbuf)); @@ -1952,7 +1952,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, if (!isleaf) { Page cpage = BufferGetPage(cbuf); - BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage); + BTPageOpaque cpageop = BTPageGetOpaque(cpage); cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; MarkBufferDirty(cbuf); @@ -2139,7 +2139,7 @@ _bt_insert_parent(Relation rel, BTPageOpaque opaque; elog(DEBUG2, "concurrent ROOT page split"); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * We should never reach here when a leaf page split takes place @@ -2230,7 +2230,7 @@ void _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack) { Page lpage = BufferGetPage(lbuf); - BTPageOpaque lpageop = (BTPageOpaque) PageGetSpecialPointer(lpage); + BTPageOpaque lpageop = BTPageGetOpaque(lpage); Buffer rbuf; Page rpage; BTPageOpaque rpageop; @@ -2242,7 +2242,7 @@ _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack) /* Lock right sibling, the one missing the downlink */ rbuf = _bt_getbuf(rel, lpageop->btpo_next, BT_WRITE); rpage = BufferGetPage(rbuf); - rpageop = (BTPageOpaque) PageGetSpecialPointer(rpage); + rpageop = BTPageGetOpaque(rpage); /* Could this be a root split? */ if (!stack) @@ -2320,7 +2320,7 @@ _bt_getstackbuf(Relation rel, BTStack stack, BlockNumber child) buf = _bt_getbuf(rel, blkno, BT_WRITE); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_INCOMPLETE_SPLIT(opaque)) { @@ -2451,7 +2451,7 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf) lbkno = BufferGetBlockNumber(lbuf); rbkno = BufferGetBlockNumber(rbuf); lpage = BufferGetPage(lbuf); - lopaque = (BTPageOpaque) PageGetSpecialPointer(lpage); + lopaque = BTPageGetOpaque(lpage); /* get a new root page */ rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE); @@ -2492,11 +2492,11 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf) _bt_upgrademetapage(metapg); /* set btree special data */ - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE; rootopaque->btpo_flags = BTP_ROOT; rootopaque->btpo_level = - ((BTPageOpaque) PageGetSpecialPointer(lpage))->btpo_level + 1; + (BTPageGetOpaque(lpage))->btpo_level + 1; rootopaque->btpo_cycleid = 0; /* update metapage data */ @@ -2680,7 +2680,7 @@ _bt_delete_or_dedup_one_page(Relation rel, Relation heapRel, Buffer buffer = insertstate->buf; BTScanInsert itup_key = insertstate->itup_key; Page page = BufferGetPage(buffer); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); Assert(simpleonly || itup_key->heapkeyspace); diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c index 6b5f01e1d0..20adb602a4 100644 --- a/src/backend/access/nbtree/nbtpage.c +++ b/src/backend/access/nbtree/nbtpage.c @@ -85,7 +85,7 @@ _bt_initmetapage(Page page, BlockNumber rootbknum, uint32 level, metad->btm_last_cleanup_num_heap_tuples = -1.0; metad->btm_allequalimage = allequalimage; - metaopaque = (BTPageOpaque) PageGetSpecialPointer(page); + metaopaque = BTPageGetOpaque(page); metaopaque->btpo_flags = BTP_META; /* @@ -112,7 +112,7 @@ _bt_upgrademetapage(Page page) BTPageOpaque metaopaque PG_USED_FOR_ASSERTS_ONLY; metad = BTPageGetMeta(page); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(page); + metaopaque = BTPageGetOpaque(page); /* It must be really a meta page of upgradable version */ Assert(metaopaque->btpo_flags & BTP_META); @@ -148,7 +148,7 @@ _bt_getmeta(Relation rel, Buffer metabuf) BTMetaPageData *metad; metapg = BufferGetPage(metabuf); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg); + metaopaque = BTPageGetOpaque(metapg); metad = BTPageGetMeta(metapg); /* sanity-check the metapage */ @@ -372,7 +372,7 @@ _bt_getroot(Relation rel, int access) rootbuf = _bt_getbuf(rel, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); /* * Since the cache might be stale, we check the page more carefully @@ -440,7 +440,7 @@ _bt_getroot(Relation rel, int access) rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE); rootblkno = BufferGetBlockNumber(rootbuf); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE; rootopaque->btpo_flags = (BTP_LEAF | BTP_ROOT); rootopaque->btpo_level = 0; @@ -534,7 +534,7 @@ _bt_getroot(Relation rel, int access) { rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); if (!P_IGNORE(rootopaque)) break; @@ -598,7 +598,7 @@ _bt_gettrueroot(Relation rel) metabuf = _bt_getbuf(rel, BTREE_METAPAGE, BT_READ); metapg = BufferGetPage(metabuf); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg); + metaopaque = BTPageGetOpaque(metapg); metad = BTPageGetMeta(metapg); if (!P_ISMETA(metaopaque) || @@ -637,7 +637,7 @@ _bt_gettrueroot(Relation rel) { rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); if (!P_IGNORE(rootopaque)) break; @@ -1220,7 +1220,7 @@ _bt_delitems_vacuum(Relation rel, Buffer buf, * We can clear the vacuum cycle ID since this page has certainly been * processed by the current vacuum scan. */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_cycleid = 0; /* @@ -1338,7 +1338,7 @@ _bt_delitems_delete(Relation rel, Buffer buf, TransactionId latestRemovedXid, * Unlike _bt_delitems_vacuum, we *must not* clear the vacuum cycle ID at * this point. The VACUUM command alone controls vacuum cycle IDs. */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Clear the BTP_HAS_GARBAGE page flag. @@ -1718,7 +1718,7 @@ _bt_leftsib_splitflag(Relation rel, BlockNumber leftsib, BlockNumber target) buf = _bt_getbuf(rel, leftsib, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If the left sibling was concurrently split, so that its next-pointer @@ -1773,7 +1773,7 @@ _bt_rightsib_halfdeadflag(Relation rel, BlockNumber leafrightsib) buf = _bt_getbuf(rel, leafrightsib, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque)); result = P_ISHALFDEAD(opaque); @@ -1842,7 +1842,7 @@ _bt_pagedel(Relation rel, Buffer leafbuf, BTVacState *vstate) for (;;) { page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Internal pages are never deleted directly, only as part of deleting @@ -2099,7 +2099,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) IndexTupleData trunctuple; page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(!P_RIGHTMOST(opaque) && !P_ISROOT(opaque) && P_ISLEAF(opaque) && !P_IGNORE(opaque) && @@ -2154,7 +2154,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * before entering the critical section --- otherwise it'd be a PANIC. */ page = BufferGetPage(subtreeparent); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); #ifdef USE_ASSERT_CHECKING @@ -2201,7 +2201,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * nbtree/README. */ page = BufferGetPage(subtreeparent); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); itemid = PageGetItemId(page, poffset); itup = (IndexTuple) PageGetItem(page, itemid); @@ -2216,7 +2216,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * is set to InvalidBlockNumber. */ page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags |= BTP_HALF_DEAD; Assert(PageGetMaxOffsetNumber(page) == P_HIKEY); @@ -2253,7 +2253,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) XLogRegisterBuffer(1, subtreeparent, REGBUF_STANDARD); page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); xlrec.leftblk = opaque->btpo_prev; xlrec.rightblk = opaque->btpo_next; @@ -2325,7 +2325,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, BlockNumber leaftopparent; page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque) && P_ISHALFDEAD(opaque)); @@ -2364,7 +2364,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* Fetch the block number of the target's left sibling */ buf = _bt_getbuf(rel, target, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); leftsib = opaque->btpo_prev; targetlevel = opaque->btpo_level; Assert(targetlevel > 0); @@ -2391,7 +2391,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, { lbuf = _bt_getbuf(rel, leftsib, BT_WRITE); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); while (P_ISDELETED(opaque) || opaque->btpo_next != target) { bool leftsibvalid = true; @@ -2441,7 +2441,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* step right one page */ lbuf = _bt_getbuf(rel, leftsib, BT_WRITE); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } } else @@ -2450,7 +2450,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* Next write-lock the target page itself */ _bt_lockbuf(rel, buf, BT_WRITE); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Check page is still empty etc, else abandon deletion. This is just for @@ -2505,7 +2505,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, rightsib = opaque->btpo_next; rbuf = _bt_getbuf(rel, rightsib, BT_WRITE); page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (opaque->btpo_prev != target) ereport(ERROR, (errcode(ERRCODE_INDEX_CORRUPTED), @@ -2528,7 +2528,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, if (leftsib == P_NONE && rightsib_is_rightmost) { page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_RIGHTMOST(opaque)) { /* rightsib will be the only one left on the level */ @@ -2565,12 +2565,12 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, if (BufferIsValid(lbuf)) { page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(opaque->btpo_next == target); opaque->btpo_next = rightsib; } page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(opaque->btpo_prev == target); opaque->btpo_prev = leftsib; @@ -2599,7 +2599,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, * of that scan. */ page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISHALFDEAD(opaque) || !P_ISLEAF(opaque)); /* @@ -2814,7 +2814,7 @@ _bt_lock_subtree_parent(Relation rel, BlockNumber child, BTStack stack, parentoffset = stack->bts_offset; page = BufferGetPage(pbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); leftsibparent = opaque->btpo_prev; diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c index c9b4964c1e..07600b86fb 100644 --- a/src/backend/access/nbtree/nbtree.c +++ b/src/backend/access/nbtree/nbtree.c @@ -1070,7 +1070,7 @@ backtrack: if (!PageIsNew(page)) { _bt_checkpage(rel, buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } Assert(blkno <= scanblkno); diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c index 9d82d4904d..c74543bfde 100644 --- a/src/backend/access/nbtree/nbtsearch.c +++ b/src/backend/access/nbtree/nbtsearch.c @@ -134,7 +134,7 @@ _bt_search(Relation rel, BTScanInsert key, Buffer *bufP, int access, /* if this is a leaf page, we're done */ page = BufferGetPage(*bufP); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISLEAF(opaque)) break; @@ -268,7 +268,7 @@ _bt_moveright(Relation rel, { page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_RIGHTMOST(opaque)) break; @@ -347,7 +347,7 @@ _bt_binsrch(Relation rel, cmpval; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Requesting nextkey semantics while using scantid seems nonsensical */ Assert(!key->nextkey || key->scantid == NULL); @@ -451,7 +451,7 @@ _bt_binsrch_insert(Relation rel, BTInsertState insertstate) cmpval; page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); Assert(!key->nextkey); @@ -659,7 +659,7 @@ _bt_compare(Relation rel, OffsetNumber offnum) { TupleDesc itupdesc = RelationGetDescr(rel); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); IndexTuple itup; ItemPointer heapTid; ScanKey scankey; @@ -1536,7 +1536,7 @@ _bt_readpage(IndexScanDesc scan, ScanDirection dir, OffsetNumber offnum) Assert(BufferIsValid(so->currPos.buf)); page = BufferGetPage(so->currPos.buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* allow next page be processed by parallel worker */ if (scan->parallel_scan) @@ -2007,7 +2007,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir) so->currPos.buf = _bt_getbuf(rel, blkno, BT_READ); page = BufferGetPage(so->currPos.buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* check for deleted page */ if (!P_IGNORE(opaque)) { @@ -2110,7 +2110,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir) */ page = BufferGetPage(so->currPos.buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_IGNORE(opaque)) { PredicateLockPage(rel, BufferGetBlockNumber(so->currPos.buf), scan->xs_snapshot); @@ -2191,7 +2191,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) BTPageOpaque opaque; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); for (;;) { @@ -2216,7 +2216,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_getbuf(rel, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If this isn't the page we want, walk right till we find what we @@ -2243,14 +2243,14 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } /* Return to the original page to see what's up */ buf = _bt_relandgetbuf(rel, buf, obknum, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* @@ -2268,7 +2268,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_ISDELETED(opaque)) break; } @@ -2329,7 +2329,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); for (;;) { @@ -2349,7 +2349,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } /* Done? */ @@ -2372,7 +2372,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } return buf; @@ -2418,7 +2418,7 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); if (ScanDirectionIsForward(dir)) diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index 8a19de2f66..c074513efa 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -625,7 +625,7 @@ _bt_blnewpage(uint32 level) _bt_pageinit(page, BLCKSZ); /* Initialize BT opaque state */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_prev = opaque->btpo_next = P_NONE; opaque->btpo_level = level; opaque->btpo_flags = (level > 0) ? 0 : BTP_LEAF; @@ -1000,9 +1000,9 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup, Assert((BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) <= IndexRelationGetNumberOfKeyAttributes(wstate->index) && BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) > 0) || - P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage))); + P_LEFTMOST(BTPageGetOpaque(opage))); Assert(BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) == 0 || - !P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage))); + !P_LEFTMOST(BTPageGetOpaque(opage))); BTreeTupleSetDownLink(state->btps_lowkey, oblkno); _bt_buildadd(wstate, state->btps_next, state->btps_lowkey, 0); pfree(state->btps_lowkey); @@ -1017,8 +1017,8 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup, * Set the sibling links for both pages. */ { - BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(opage); - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(npage); + BTPageOpaque oopaque = BTPageGetOpaque(opage); + BTPageOpaque nopaque = BTPageGetOpaque(npage); oopaque->btpo_next = nblkno; nopaque->btpo_prev = oblkno; @@ -1125,7 +1125,7 @@ _bt_uppershutdown(BTWriteState *wstate, BTPageState *state) BTPageOpaque opaque; blkno = s->btps_blkno; - opaque = (BTPageOpaque) PageGetSpecialPointer(s->btps_page); + opaque = BTPageGetOpaque(s->btps_page); /* * We have to link the last page on this level to somewhere. diff --git a/src/backend/access/nbtree/nbtsplitloc.c b/src/backend/access/nbtree/nbtsplitloc.c index c46594e1a2..ee01ceafda 100644 --- a/src/backend/access/nbtree/nbtsplitloc.c +++ b/src/backend/access/nbtree/nbtsplitloc.c @@ -152,7 +152,7 @@ _bt_findsplitloc(Relation rel, SplitPoint leftpage, rightpage; - opaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + opaque = BTPageGetOpaque(origpage); maxoff = PageGetMaxOffsetNumber(origpage); /* Total free space available on a btree page, after fixed overhead */ diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c index 84164748b3..96c72fc432 100644 --- a/src/backend/access/nbtree/nbtutils.c +++ b/src/backend/access/nbtree/nbtutils.c @@ -1774,7 +1774,7 @@ _bt_killitems(IndexScanDesc scan) } } - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); minoff = P_FIRSTDATAKEY(opaque); maxoff = PageGetMaxOffsetNumber(page); @@ -2474,7 +2474,7 @@ _bt_check_natts(Relation rel, bool heapkeyspace, Page page, OffsetNumber offnum) { int16 natts = IndexRelationGetNumberOfAttributes(rel); int16 nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); IndexTuple itup; int tupnatts; @@ -2662,7 +2662,7 @@ _bt_check_third_page(Relation rel, Relation heap, bool needheaptidspace, * Internal page insertions cannot fail here, because that would mean that * an earlier leaf level insertion that should have failed didn't */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_ISLEAF(opaque)) elog(ERROR, "cannot insert oversized tuple of size %zu on internal page of index \"%s\"", itemsz, RelationGetRelationName(rel)); diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c index 611f412ba8..fba124b940 100644 --- a/src/backend/access/nbtree/nbtxlog.c +++ b/src/backend/access/nbtree/nbtxlog.c @@ -115,7 +115,7 @@ _bt_restore_meta(XLogReaderState *record, uint8 block_id) md->btm_last_cleanup_num_heap_tuples = -1.0; md->btm_allequalimage = xlrec->allequalimage; - pageop = (BTPageOpaque) PageGetSpecialPointer(metapg); + pageop = BTPageGetOpaque(metapg); pageop->btpo_flags = BTP_META; /* @@ -146,7 +146,7 @@ _bt_clear_incomplete_split(XLogReaderState *record, uint8 block_id) if (XLogReadBufferForRedo(record, block_id, &buf) == BLK_NEEDS_REDO) { Page page = (Page) BufferGetPage(buf); - BTPageOpaque pageop = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque pageop = BTPageGetOpaque(page); Assert(P_INCOMPLETE_SPLIT(pageop)); pageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; @@ -292,7 +292,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) rpage = (Page) BufferGetPage(rbuf); _bt_pageinit(rpage, BufferGetPageSize(rbuf)); - ropaque = (BTPageOpaque) PageGetSpecialPointer(rpage); + ropaque = BTPageGetOpaque(rpage); ropaque->btpo_prev = origpagenumber; ropaque->btpo_next = spagenumber; @@ -317,7 +317,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) * same for the right page. */ Page origpage = (Page) BufferGetPage(buf); - BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + BTPageOpaque oopaque = BTPageGetOpaque(origpage); OffsetNumber off; IndexTuple newitem = NULL, left_hikey = NULL, @@ -442,7 +442,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) if (XLogReadBufferForRedo(record, 2, &sbuf) == BLK_NEEDS_REDO) { Page spage = (Page) BufferGetPage(sbuf); - BTPageOpaque spageop = (BTPageOpaque) PageGetSpecialPointer(spage); + BTPageOpaque spageop = BTPageGetOpaque(spage); spageop->btpo_prev = rightpagenumber; @@ -473,7 +473,7 @@ btree_xlog_dedup(XLogReaderState *record) { char *ptr = XLogRecGetBlockData(record, 0, NULL); Page page = (Page) BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); OffsetNumber offnum, minoff, maxoff; @@ -541,7 +541,7 @@ btree_xlog_dedup(XLogReaderState *record) if (P_HAS_GARBAGE(opaque)) { - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage); + BTPageOpaque nopaque = BTPageGetOpaque(newpage); nopaque->btpo_flags &= ~BTP_HAS_GARBAGE; } @@ -639,7 +639,7 @@ btree_xlog_vacuum(XLogReaderState *record) * Mark the page as not containing any LP_DEAD items --- see comments * in _bt_delitems_vacuum(). */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags &= ~BTP_HAS_GARBAGE; PageSetLSN(page, lsn); @@ -699,7 +699,7 @@ btree_xlog_delete(XLogReaderState *record) PageIndexMultiDelete(page, (OffsetNumber *) ptr, xlrec->ndeleted); /* Mark the page as not containing any LP_DEAD items */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags &= ~BTP_HAS_GARBAGE; PageSetLSN(page, lsn); @@ -737,7 +737,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record) BlockNumber rightsib; page = (Page) BufferGetPage(buffer); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); poffset = xlrec->poffset; @@ -768,7 +768,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(buffer); _bt_pageinit(page, BufferGetPageSize(buffer)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = xlrec->leftblk; pageop->btpo_next = xlrec->rightblk; @@ -833,7 +833,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) if (XLogReadBufferForRedo(record, 1, &leftbuf) == BLK_NEEDS_REDO) { page = (Page) BufferGetPage(leftbuf); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_next = rightsib; PageSetLSN(page, lsn); @@ -848,7 +848,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(target); _bt_pageinit(page, BufferGetPageSize(target)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = leftsib; pageop->btpo_next = rightsib; @@ -865,7 +865,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) if (XLogReadBufferForRedo(record, 2, &rightbuf) == BLK_NEEDS_REDO) { page = (Page) BufferGetPage(rightbuf); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = leftsib; PageSetLSN(page, lsn); @@ -906,7 +906,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(leafbuf); _bt_pageinit(page, BufferGetPageSize(leafbuf)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_flags = BTP_HALF_DEAD | BTP_LEAF; pageop->btpo_prev = xlrec->leafleftsib; @@ -948,7 +948,7 @@ btree_xlog_newroot(XLogReaderState *record) page = (Page) BufferGetPage(buffer); _bt_pageinit(page, BufferGetPageSize(buffer)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_flags = BTP_ROOT; pageop->btpo_prev = pageop->btpo_next = P_NONE; @@ -1097,7 +1097,7 @@ btree_mask(char *pagedata, BlockNumber blkno) mask_page_hint_bits(page); mask_unused_space(page); - maskopaq = (BTPageOpaque) PageGetSpecialPointer(page); + maskopaq = BTPageGetOpaque(page); if (P_ISLEAF(maskopaq)) { diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h index 9fec6fb1a8..31edddefc0 100644 --- a/src/include/access/nbtree.h +++ b/src/include/access/nbtree.h @@ -70,6 +70,13 @@ typedef struct BTPageOpaqueData typedef BTPageOpaqueData *BTPageOpaque; +/* + * Pre-aligned accessor to the opaque data in the page's special region. + * Avoids data dependency on page header in non-assert builds. + */ +#define BTPageGetOpaque(page) \ + ((BTPageOpaque) PageGetSpecialOpaque((page), BTPageOpaqueData)) + /* Bits defined in btpo_flags */ #define BTP_LEAF (1 << 0) /* leaf page, i.e. not internal page */ #define BTP_ROOT (1 << 1) /* root page (has no parent) */ @@ -241,7 +248,7 @@ BTPageSetDeleted(Page page, FullTransactionId safexid) PageHeader header; BTDeletedPageData *contents; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); header = ((PageHeader) page); opaque->btpo_flags &= ~BTP_HALF_DEAD; @@ -263,7 +270,7 @@ BTPageGetDeleteXid(Page page) /* We only expect to be called with a deleted page */ Assert(!PageIsNew(page)); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISDELETED(opaque)); /* pg_upgrade'd deleted page -- must be safe to delete now */ @@ -294,7 +301,7 @@ BTPageIsRecyclable(Page page) Assert(!PageIsNew(page)); /* Recycling okay iff page is deleted and safexid is old enough */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* -- 2.30.2 [application/x-patch] v2-0003-Update-hash-code-to-use-PageGetSpecialOpaque-repl.patch (22.5K, ../../CAEze2Wjjx4REsge5kxNjDjKDVvkqbruqxVLykxj_UufZ0xzbOw@mail.gmail.com/4-v2-0003-Update-hash-code-to-use-PageGetSpecialOpaque-repl.patch) download | inline diff: From b666d9c52c5d47fa66e453d7e2dbb474956a0bff Mon Sep 17 00:00:00 2001 From: Matthias van de Meent <[email protected]> Date: Mon, 28 Mar 2022 16:45:52 +0200 Subject: [PATCH v2 3/3] Update hash code to use PageGetSpecialOpaque; replace PageGetSpecialPointer+cast As in the earlier patch, this reduces memory access requirements by directly reading into the target space instead of needing to access the header of the page first. Also makes the code a lot more readable by replacing templated macro+casts with a single macro specialized for hash page opaques. --- contrib/pageinspect/hashfuncs.c | 6 +++--- contrib/pgstattuple/pgstatindex.c | 2 +- contrib/pgstattuple/pgstattuple.c | 2 +- src/backend/access/hash/hash.c | 6 +++--- src/backend/access/hash/hash_xlog.c | 26 ++++++++++++------------ src/backend/access/hash/hashinsert.c | 6 +++--- src/backend/access/hash/hashovfl.c | 22 ++++++++++---------- src/backend/access/hash/hashpage.c | 30 ++++++++++++++-------------- src/backend/access/hash/hashsearch.c | 12 +++++------ src/backend/access/hash/hashutil.c | 4 ++-- src/include/access/hash.h | 3 +++ 11 files changed, 61 insertions(+), 58 deletions(-) diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c index 6de21d6608..69af7b962f 100644 --- a/contrib/pageinspect/hashfuncs.c +++ b/contrib/pageinspect/hashfuncs.c @@ -72,7 +72,7 @@ verify_hash_page(bytea *raw_page, int flags) (int) MAXALIGN(sizeof(HashPageOpaqueData)), (int) PageGetSpecialSize(page)))); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); if (pageopaque->hasho_page_id != HASHO_PAGE_ID) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), @@ -154,7 +154,7 @@ static void GetHashPageStatistics(Page page, HashPageStat *stat) { OffsetNumber maxoff = PageGetMaxOffsetNumber(page); - HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page); + HashPageOpaque opaque = HashPageGetOpaque(page); int off; stat->dead_items = stat->live_items = 0; @@ -206,7 +206,7 @@ hash_page_type(PG_FUNCTION_ARGS) type = "unused"; else { - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); /* page type (flags) */ pagetype = opaque->hasho_flag & LH_PAGE_TYPE; diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c index b9939451b4..e1048e47ff 100644 --- a/contrib/pgstattuple/pgstatindex.c +++ b/contrib/pgstattuple/pgstatindex.c @@ -641,7 +641,7 @@ pgstathashindex(PG_FUNCTION_ARGS) HashPageOpaque opaque; int pagetype; - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); pagetype = opaque->hasho_flag & LH_PAGE_TYPE; if (pagetype == LH_BUCKET_PAGE) diff --git a/contrib/pgstattuple/pgstattuple.c b/contrib/pgstattuple/pgstattuple.c index a9658d389b..3094566908 100644 --- a/contrib/pgstattuple/pgstattuple.c +++ b/contrib/pgstattuple/pgstattuple.c @@ -452,7 +452,7 @@ pgstat_hash_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno, { HashPageOpaque opaque; - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); switch (opaque->hasho_flag & LH_PAGE_TYPE) { case LH_UNUSED_PAGE: diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c index a259a301fa..fd1a7119b6 100644 --- a/src/backend/access/hash/hash.c +++ b/src/backend/access/hash/hash.c @@ -515,7 +515,7 @@ loop_top: _hash_checkpage(rel, buf, LH_BUCKET_PAGE); page = BufferGetPage(buf); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); /* * If the bucket contains tuples that are moved by split, then we need @@ -717,7 +717,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf, vacuum_delay_point(); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); /* Scan each tuple in page */ maxoffno = PageGetMaxOffsetNumber(page); @@ -884,7 +884,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf, Page page; page = BufferGetPage(bucket_buf); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); /* No ereport(ERROR) until changes are logged */ START_CRIT_SECTION(); diff --git a/src/backend/access/hash/hash_xlog.c b/src/backend/access/hash/hash_xlog.c index 55937b9a68..62dbfc3a5d 100644 --- a/src/backend/access/hash/hash_xlog.c +++ b/src/backend/access/hash/hash_xlog.c @@ -203,7 +203,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record) true); /* update backlink */ ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = leftblk; PageSetLSN(ovflpage, lsn); @@ -215,7 +215,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record) HashPageOpaque leftopaque; leftpage = BufferGetPage(leftbuf); - leftopaque = (HashPageOpaque) PageGetSpecialPointer(leftpage); + leftopaque = HashPageGetOpaque(leftpage); leftopaque->hasho_nextblkno = rightblk; PageSetLSN(leftpage, lsn); @@ -342,7 +342,7 @@ hash_xlog_split_allocate_page(XLogReaderState *record) HashPageOpaque oldopaque; oldpage = BufferGetPage(oldbuf); - oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage); + oldopaque = HashPageGetOpaque(oldpage); oldopaque->hasho_flag = xlrec->old_bucket_flag; oldopaque->hasho_prevblkno = xlrec->new_bucket; @@ -465,7 +465,7 @@ hash_xlog_split_complete(XLogReaderState *record) HashPageOpaque oldopaque; oldpage = BufferGetPage(oldbuf); - oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage); + oldopaque = HashPageGetOpaque(oldpage); oldopaque->hasho_flag = xlrec->old_bucket_flag; @@ -488,7 +488,7 @@ hash_xlog_split_complete(XLogReaderState *record) HashPageOpaque nopaque; newpage = BufferGetPage(newbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(newpage); + nopaque = HashPageGetOpaque(newpage); nopaque->hasho_flag = xlrec->new_bucket_flag; @@ -710,7 +710,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) */ if (xldata->is_prev_bucket_same_wrt) { - HashPageOpaque writeopaque = (HashPageOpaque) PageGetSpecialPointer(writepage); + HashPageOpaque writeopaque = HashPageGetOpaque(writepage); writeopaque->hasho_nextblkno = xldata->nextblkno; } @@ -729,7 +729,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) _hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf)); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -748,7 +748,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) XLogReadBufferForRedo(record, 3, &prevbuf) == BLK_NEEDS_REDO) { Page prevpage = BufferGetPage(prevbuf); - HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage); + HashPageOpaque prevopaque = HashPageGetOpaque(prevpage); prevopaque->hasho_nextblkno = xldata->nextblkno; @@ -766,7 +766,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) if (XLogReadBufferForRedo(record, 4, &nextbuf) == BLK_NEEDS_REDO) { Page nextpage = BufferGetPage(nextbuf); - HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage); + HashPageOpaque nextopaque = HashPageGetOpaque(nextpage); nextopaque->hasho_prevblkno = xldata->prevblkno; @@ -903,7 +903,7 @@ hash_xlog_delete(XLogReaderState *record) { HashPageOpaque pageopaque; - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; } @@ -933,7 +933,7 @@ hash_xlog_split_cleanup(XLogReaderState *record) page = (Page) BufferGetPage(buffer); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); bucket_opaque->hasho_flag &= ~LH_BUCKET_NEEDS_SPLIT_CLEANUP; PageSetLSN(page, lsn); MarkBufferDirty(buffer); @@ -1024,7 +1024,7 @@ hash_xlog_vacuum_one_page(XLogReaderState *record) * Mark the page as not containing any LP_DEAD items. See comments in * _hash_vacuum_one_page() for details. */ - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; PageSetLSN(page, lsn); @@ -1116,7 +1116,7 @@ hash_mask(char *pagedata, BlockNumber blkno) mask_page_hint_bits(page); mask_unused_space(page); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); pagetype = opaque->hasho_flag & LH_PAGE_TYPE; if (pagetype == LH_UNUSED_PAGE) diff --git a/src/backend/access/hash/hashinsert.c b/src/backend/access/hash/hashinsert.c index faf609c157..4f2fecb908 100644 --- a/src/backend/access/hash/hashinsert.c +++ b/src/backend/access/hash/hashinsert.c @@ -95,7 +95,7 @@ restart_insert: bucket_buf = buf; page = BufferGetPage(buf); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); bucket = pageopaque->hasho_bucket; /* @@ -183,7 +183,7 @@ restart_insert: /* should fit now, given test above */ Assert(PageGetFreeSpace(page) >= itemsz); } - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); Assert((pageopaque->hasho_flag & LH_PAGE_TYPE) == LH_OVERFLOW_PAGE); Assert(pageopaque->hasho_bucket == bucket); } @@ -384,7 +384,7 @@ _hash_vacuum_one_page(Relation rel, Relation hrel, Buffer metabuf, Buffer buf) * check it. Remember that LH_PAGE_HAS_DEAD_TUPLES is only a hint * anyway. */ - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; metap = HashPageGetMeta(BufferGetPage(metabuf)); diff --git a/src/backend/access/hash/hashovfl.c b/src/backend/access/hash/hashovfl.c index 4836875196..e34cfc302d 100644 --- a/src/backend/access/hash/hashovfl.c +++ b/src/backend/access/hash/hashovfl.c @@ -159,7 +159,7 @@ _hash_addovflpage(Relation rel, Buffer metabuf, Buffer buf, bool retain_pin) BlockNumber nextblkno; page = BufferGetPage(buf); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); nextblkno = pageopaque->hasho_nextblkno; if (!BlockNumberIsValid(nextblkno)) @@ -364,7 +364,7 @@ found: /* initialize new overflow page */ ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = BufferGetBlockNumber(buf); ovflopaque->hasho_nextblkno = InvalidBlockNumber; ovflopaque->hasho_bucket = pageopaque->hasho_bucket; @@ -516,7 +516,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, _hash_checkpage(rel, ovflbuf, LH_OVERFLOW_PAGE); ovflblkno = BufferGetBlockNumber(ovflbuf); ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); nextblkno = ovflopaque->hasho_nextblkno; prevblkno = ovflopaque->hasho_prevblkno; writeblkno = BufferGetBlockNumber(wbuf); @@ -600,7 +600,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, */ _hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf)); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -613,7 +613,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, if (BufferIsValid(prevbuf)) { Page prevpage = BufferGetPage(prevbuf); - HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage); + HashPageOpaque prevopaque = HashPageGetOpaque(prevpage); Assert(prevopaque->hasho_bucket == bucket); prevopaque->hasho_nextblkno = nextblkno; @@ -622,7 +622,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, if (BufferIsValid(nextbuf)) { Page nextpage = BufferGetPage(nextbuf); - HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage); + HashPageOpaque nextopaque = HashPageGetOpaque(nextpage); Assert(nextopaque->hasho_bucket == bucket); nextopaque->hasho_prevblkno = prevblkno; @@ -751,7 +751,7 @@ _hash_initbitmapbuffer(Buffer buf, uint16 bmsize, bool initpage) _hash_pageinit(pg, BufferGetPageSize(buf)); /* initialize the page's special space */ - op = (HashPageOpaque) PageGetSpecialPointer(pg); + op = HashPageGetOpaque(pg); op->hasho_prevblkno = InvalidBlockNumber; op->hasho_nextblkno = InvalidBlockNumber; op->hasho_bucket = InvalidBucket; @@ -824,7 +824,7 @@ _hash_squeezebucket(Relation rel, wblkno = bucket_blkno; wbuf = bucket_buf; wpage = BufferGetPage(wbuf); - wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage); + wopaque = HashPageGetOpaque(wpage); /* * if there aren't any overflow pages, there's nothing to squeeze. caller @@ -855,7 +855,7 @@ _hash_squeezebucket(Relation rel, LH_OVERFLOW_PAGE, bstrategy); rpage = BufferGetPage(rbuf); - ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage); + ropaque = HashPageGetOpaque(rpage); Assert(ropaque->hasho_bucket == bucket); } while (BlockNumberIsValid(ropaque->hasho_nextblkno)); @@ -1005,7 +1005,7 @@ readpage: wbuf = next_wbuf; wpage = BufferGetPage(wbuf); - wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage); + wopaque = HashPageGetOpaque(wpage); Assert(wopaque->hasho_bucket == bucket); retain_pin = false; @@ -1076,7 +1076,7 @@ readpage: LH_OVERFLOW_PAGE, bstrategy); rpage = BufferGetPage(rbuf); - ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage); + ropaque = HashPageGetOpaque(rpage); Assert(ropaque->hasho_bucket == bucket); } diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c index 28c5297a1d..39206d1942 100644 --- a/src/backend/access/hash/hashpage.c +++ b/src/backend/access/hash/hashpage.c @@ -166,7 +166,7 @@ _hash_initbuf(Buffer buf, uint32 max_bucket, uint32 num_bucket, uint32 flag, if (initpage) _hash_pageinit(page, BufferGetPageSize(buf)); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); /* * Set hasho_prevblkno with current hashm_maxbucket. This value will be @@ -529,7 +529,7 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid, if (initpage) _hash_pageinit(page, BufferGetPageSize(buf)); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_prevblkno = InvalidBlockNumber; pageopaque->hasho_nextblkno = InvalidBlockNumber; pageopaque->hasho_bucket = InvalidBucket; @@ -693,7 +693,7 @@ restart_expand: goto fail; opage = BufferGetPage(buf_oblkno); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); /* * We want to finish the split from a bucket as there is no apparent @@ -864,7 +864,7 @@ restart_expand: lowmask = metap->hashm_lowmask; opage = BufferGetPage(buf_oblkno); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); /* * Mark the old bucket to indicate that split is in progress. (At @@ -883,7 +883,7 @@ restart_expand: * initialize the new bucket's primary page and mark it to indicate that * split is in progress. */ - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); nopaque->hasho_prevblkno = maxbucket; nopaque->hasho_nextblkno = InvalidBlockNumber; nopaque->hasho_bucket = new_bucket; @@ -1010,7 +1010,7 @@ _hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks) */ _hash_pageinit(page, BLCKSZ); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(page); + ovflopaque = HashPageGetOpaque(page); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -1091,11 +1091,11 @@ _hash_splitbucket(Relation rel, bucket_obuf = obuf; opage = BufferGetPage(obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); bucket_nbuf = nbuf; npage = BufferGetPage(nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); /* Copy the predicate locks from old bucket to new bucket. */ PredicateLockPageSplit(rel, @@ -1198,7 +1198,7 @@ _hash_splitbucket(Relation rel, /* chain to a new overflow page */ nbuf = _hash_addovflpage(rel, metabuf, nbuf, (nbuf == bucket_nbuf)); npage = BufferGetPage(nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); } itups[nitups++] = new_itup; @@ -1251,7 +1251,7 @@ _hash_splitbucket(Relation rel, /* Else, advance to next old page */ obuf = _hash_getbuf(rel, oblkno, HASH_READ, LH_OVERFLOW_PAGE); opage = BufferGetPage(obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); } /* @@ -1264,11 +1264,11 @@ _hash_splitbucket(Relation rel, */ LockBuffer(bucket_obuf, BUFFER_LOCK_EXCLUSIVE); opage = BufferGetPage(bucket_obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); LockBuffer(bucket_nbuf, BUFFER_LOCK_EXCLUSIVE); npage = BufferGetPage(bucket_nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); START_CRIT_SECTION(); @@ -1392,7 +1392,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket, bucket_nbuf = nbuf; npage = BufferGetPage(nbuf); - npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + npageopaque = HashPageGetOpaque(npage); /* Scan each tuple in new page */ nmaxoffnum = PageGetMaxOffsetNumber(npage); @@ -1446,7 +1446,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket, } npage = BufferGetPage(bucket_nbuf); - npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + npageopaque = HashPageGetOpaque(npage); nbucket = npageopaque->hasho_bucket; _hash_splitbucket(rel, metabuf, obucket, @@ -1587,7 +1587,7 @@ _hash_getbucketbuf_from_hashkey(Relation rel, uint32 hashkey, int access, /* Fetch the primary bucket page for the bucket */ buf = _hash_getbuf(rel, blkno, access, LH_BUCKET_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); Assert(opaque->hasho_bucket == bucket); Assert(opaque->hasho_prevblkno != InvalidBlockNumber); diff --git a/src/backend/access/hash/hashsearch.c b/src/backend/access/hash/hashsearch.c index 7ca542a3fb..524af27409 100644 --- a/src/backend/access/hash/hashsearch.c +++ b/src/backend/access/hash/hashsearch.c @@ -187,7 +187,7 @@ _hash_readnext(IndexScanDesc scan, { *pagep = BufferGetPage(*bufp); TestForOldSnapshot(scan->xs_snapshot, rel, *pagep); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); } } @@ -233,7 +233,7 @@ _hash_readprev(IndexScanDesc scan, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE); *pagep = BufferGetPage(*bufp); TestForOldSnapshot(scan->xs_snapshot, rel, *pagep); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); /* * We always maintain the pin on bucket page for whole scan operation, @@ -258,7 +258,7 @@ _hash_readprev(IndexScanDesc scan, LockBuffer(*bufp, BUFFER_LOCK_SHARE); *pagep = BufferGetPage(*bufp); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); /* move to the end of bucket chain */ while (BlockNumberIsValid((*opaquep)->hasho_nextblkno)) @@ -352,7 +352,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir) PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot); page = BufferGetPage(buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); bucket = opaque->hasho_bucket; so->hashso_bucket_buf = buf; @@ -398,7 +398,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir) LockBuffer(buf, BUFFER_LOCK_SHARE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); Assert(opaque->hasho_bucket == bucket); if (H_BUCKET_BEING_POPULATED(opaque)) @@ -463,7 +463,7 @@ _hash_readpage(IndexScanDesc scan, Buffer *bufP, ScanDirection dir) Assert(BufferIsValid(buf)); _hash_checkpage(rel, buf, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); so->currPos.buf = buf; so->currPos.currPage = BufferGetBlockNumber(buf); diff --git a/src/backend/access/hash/hashutil.c b/src/backend/access/hash/hashutil.c index edb6fa968f..fe37bc47cb 100644 --- a/src/backend/access/hash/hashutil.c +++ b/src/backend/access/hash/hashutil.c @@ -239,7 +239,7 @@ _hash_checkpage(Relation rel, Buffer buf, int flags) if (flags) { - HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page); + HashPageOpaque opaque = HashPageGetOpaque(page); if ((opaque->hasho_flag & flags) == 0) ereport(ERROR, @@ -574,7 +574,7 @@ _hash_kill_items(IndexScanDesc scan) buf = _hash_getbuf(rel, blkno, HASH_READ, LH_OVERFLOW_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); for (i = 0; i < numKilled; i++) diff --git a/src/include/access/hash.h b/src/include/access/hash.h index cd7b2a53d8..d3fd8bf239 100644 --- a/src/include/access/hash.h +++ b/src/include/access/hash.h @@ -85,6 +85,9 @@ typedef struct HashPageOpaqueData typedef HashPageOpaqueData *HashPageOpaque; +#define HashPageGetOpaque(page) \ + ((HashPageOpaque) PageGetSpecialOpaque((page), HashPageOpaqueData)) + #define H_NEEDS_SPLIT_CLEANUP(opaque) (((opaque)->hasho_flag & LH_BUCKET_NEEDS_SPLIT_CLEANUP) != 0) #define H_BUCKET_BEING_SPLIT(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_SPLIT) != 0) #define H_BUCKET_BEING_POPULATED(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_POPULATED) != 0) -- 2.30.2 ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-03-31 07:32 Michael Paquier <[email protected]> parent: Matthias van de Meent <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Michael Paquier @ 2022-03-31 07:32 UTC (permalink / raw) To: Matthias van de Meent <[email protected]>; +Cc: pgsql-hackers On Mon, Mar 28, 2022 at 05:09:10PM +0200, Matthias van de Meent wrote: > Not all clusters have checksums enabled (boo!, but we can't > realistically fix that), so on-disk corruption could reasonably > propagate to the rest of such system. Additionally, checksums are only > checked on read, and updated when the page is written to disk (in > PageSetChecksumCopy called from FlushBuffer), but this does not check > for signs of page corruption. As such, a memory bug resulting in > in-memory corruption of pd_special would persist and would currently > have the potential to further corrupt neighbouring buffers. Well, if it comes to corruption then pd_special is not the only problem, just one part of it. A broken pd_lower or pd_lower or even pd_lsn could also cause AMs to point at areas they should not. There are many reasons that could make things go wrong depending on the compiled page size. >>> A second reason would be less indirection to get to the opaque >>> pointer. This should improve performance a bit in those cases where we >>> (initially) only want to access the [Index]PageOpaque struct. >> >> We don't have many cases that do that, do we? > > Indeed not many, but I know that at least the nbtree-code has some > cases where it uses the opaque before other fields in the header are > accessed (sometimes even without accessing the header for other > reasons): in _bt_moveright and _bt_walk_left. There might be more; but > these are cases I know of. Even these are marginal as the page is already loaded in the shared buffers.. While looking at the page, the pieces in 0002 and 0003 that I really liked are the introduction of the macros to grab the special area for btree and hash. This brings the code of those APIs closer to GiST, SpGiST and GIN. And it is possible to move to a possible change in the checks and/or the shape of all the *GetOpaque macros at once after the switch to this part is done. So I don't really mind introducing this part. PageGetSpecialOpaque() would not have saved the day with the recent pageinspect changes, and that's just moving the responsability of the page header to something else. I am not sure if it is a good idea to have a mention of the opaque page type in bufpage.h actually, as this is optional. Having an AssertMacro() checking that pd_special is in line with MAXALIGN(sizeof(OpaqueData)) is attractive, but I'd rather keep that in each AM's headers per its optional nature, and an index AM may handle things differently depending on a page type, as well. -- Michael Attachments: [text/x-diff] 0001-Introduce-macros-for-hash-and-btree-to-grab-their-op.patch (65.5K, ../../[email protected]/2-0001-Introduce-macros-for-hash-and-btree-to-grab-their-op.patch) download | inline diff: From e12d282461c9e4a1cba89cb7ea8e6dde90c829a6 Mon Sep 17 00:00:00 2001 From: Michael Paquier <[email protected]> Date: Thu, 31 Mar 2022 16:30:52 +0900 Subject: [PATCH] Introduce macros for hash and btree to grab their opaque area --- src/include/access/hash.h | 2 + src/include/access/nbtree.h | 8 ++-- src/backend/access/hash/hash.c | 6 +-- src/backend/access/hash/hash_xlog.c | 26 +++++------ src/backend/access/hash/hashinsert.c | 6 +-- src/backend/access/hash/hashovfl.c | 22 +++++----- src/backend/access/hash/hashpage.c | 30 ++++++------- src/backend/access/hash/hashsearch.c | 12 ++--- src/backend/access/hash/hashutil.c | 4 +- src/backend/access/nbtree/nbtdedup.c | 6 +-- src/backend/access/nbtree/nbtinsert.c | 46 ++++++++++---------- src/backend/access/nbtree/nbtpage.c | 58 ++++++++++++------------- src/backend/access/nbtree/nbtree.c | 2 +- src/backend/access/nbtree/nbtsearch.c | 34 +++++++-------- src/backend/access/nbtree/nbtsort.c | 12 ++--- src/backend/access/nbtree/nbtsplitloc.c | 2 +- src/backend/access/nbtree/nbtutils.c | 6 +-- src/backend/access/nbtree/nbtxlog.c | 34 +++++++-------- contrib/amcheck/verify_nbtree.c | 32 +++++++------- contrib/pageinspect/btreefuncs.c | 6 +-- contrib/pageinspect/hashfuncs.c | 6 +-- contrib/pgstattuple/pgstatindex.c | 4 +- contrib/pgstattuple/pgstattuple.c | 4 +- 23 files changed, 186 insertions(+), 182 deletions(-) diff --git a/src/include/access/hash.h b/src/include/access/hash.h index cd7b2a53d8..a22e328762 100644 --- a/src/include/access/hash.h +++ b/src/include/access/hash.h @@ -85,6 +85,8 @@ typedef struct HashPageOpaqueData typedef HashPageOpaqueData *HashPageOpaque; +#define HashPageGetOpaque(page) ( (HashPageOpaque) PageGetSpecialPointer(page) ) + #define H_NEEDS_SPLIT_CLEANUP(opaque) (((opaque)->hasho_flag & LH_BUCKET_NEEDS_SPLIT_CLEANUP) != 0) #define H_BUCKET_BEING_SPLIT(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_SPLIT) != 0) #define H_BUCKET_BEING_POPULATED(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_POPULATED) != 0) diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h index 9fec6fb1a8..5625a90922 100644 --- a/src/include/access/nbtree.h +++ b/src/include/access/nbtree.h @@ -70,6 +70,8 @@ typedef struct BTPageOpaqueData typedef BTPageOpaqueData *BTPageOpaque; +#define BTPageGetOpaque(page) ( (BTPageOpaque) PageGetSpecialPointer(page) ) + /* Bits defined in btpo_flags */ #define BTP_LEAF (1 << 0) /* leaf page, i.e. not internal page */ #define BTP_ROOT (1 << 1) /* root page (has no parent) */ @@ -241,7 +243,7 @@ BTPageSetDeleted(Page page, FullTransactionId safexid) PageHeader header; BTDeletedPageData *contents; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); header = ((PageHeader) page); opaque->btpo_flags &= ~BTP_HALF_DEAD; @@ -263,7 +265,7 @@ BTPageGetDeleteXid(Page page) /* We only expect to be called with a deleted page */ Assert(!PageIsNew(page)); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISDELETED(opaque)); /* pg_upgrade'd deleted page -- must be safe to delete now */ @@ -294,7 +296,7 @@ BTPageIsRecyclable(Page page) Assert(!PageIsNew(page)); /* Recycling okay iff page is deleted and safexid is old enough */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c index a259a301fa..fd1a7119b6 100644 --- a/src/backend/access/hash/hash.c +++ b/src/backend/access/hash/hash.c @@ -515,7 +515,7 @@ loop_top: _hash_checkpage(rel, buf, LH_BUCKET_PAGE); page = BufferGetPage(buf); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); /* * If the bucket contains tuples that are moved by split, then we need @@ -717,7 +717,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf, vacuum_delay_point(); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); /* Scan each tuple in page */ maxoffno = PageGetMaxOffsetNumber(page); @@ -884,7 +884,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf, Page page; page = BufferGetPage(bucket_buf); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); /* No ereport(ERROR) until changes are logged */ START_CRIT_SECTION(); diff --git a/src/backend/access/hash/hash_xlog.c b/src/backend/access/hash/hash_xlog.c index 55937b9a68..62dbfc3a5d 100644 --- a/src/backend/access/hash/hash_xlog.c +++ b/src/backend/access/hash/hash_xlog.c @@ -203,7 +203,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record) true); /* update backlink */ ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = leftblk; PageSetLSN(ovflpage, lsn); @@ -215,7 +215,7 @@ hash_xlog_add_ovfl_page(XLogReaderState *record) HashPageOpaque leftopaque; leftpage = BufferGetPage(leftbuf); - leftopaque = (HashPageOpaque) PageGetSpecialPointer(leftpage); + leftopaque = HashPageGetOpaque(leftpage); leftopaque->hasho_nextblkno = rightblk; PageSetLSN(leftpage, lsn); @@ -342,7 +342,7 @@ hash_xlog_split_allocate_page(XLogReaderState *record) HashPageOpaque oldopaque; oldpage = BufferGetPage(oldbuf); - oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage); + oldopaque = HashPageGetOpaque(oldpage); oldopaque->hasho_flag = xlrec->old_bucket_flag; oldopaque->hasho_prevblkno = xlrec->new_bucket; @@ -465,7 +465,7 @@ hash_xlog_split_complete(XLogReaderState *record) HashPageOpaque oldopaque; oldpage = BufferGetPage(oldbuf); - oldopaque = (HashPageOpaque) PageGetSpecialPointer(oldpage); + oldopaque = HashPageGetOpaque(oldpage); oldopaque->hasho_flag = xlrec->old_bucket_flag; @@ -488,7 +488,7 @@ hash_xlog_split_complete(XLogReaderState *record) HashPageOpaque nopaque; newpage = BufferGetPage(newbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(newpage); + nopaque = HashPageGetOpaque(newpage); nopaque->hasho_flag = xlrec->new_bucket_flag; @@ -710,7 +710,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) */ if (xldata->is_prev_bucket_same_wrt) { - HashPageOpaque writeopaque = (HashPageOpaque) PageGetSpecialPointer(writepage); + HashPageOpaque writeopaque = HashPageGetOpaque(writepage); writeopaque->hasho_nextblkno = xldata->nextblkno; } @@ -729,7 +729,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) _hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf)); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -748,7 +748,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) XLogReadBufferForRedo(record, 3, &prevbuf) == BLK_NEEDS_REDO) { Page prevpage = BufferGetPage(prevbuf); - HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage); + HashPageOpaque prevopaque = HashPageGetOpaque(prevpage); prevopaque->hasho_nextblkno = xldata->nextblkno; @@ -766,7 +766,7 @@ hash_xlog_squeeze_page(XLogReaderState *record) if (XLogReadBufferForRedo(record, 4, &nextbuf) == BLK_NEEDS_REDO) { Page nextpage = BufferGetPage(nextbuf); - HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage); + HashPageOpaque nextopaque = HashPageGetOpaque(nextpage); nextopaque->hasho_prevblkno = xldata->prevblkno; @@ -903,7 +903,7 @@ hash_xlog_delete(XLogReaderState *record) { HashPageOpaque pageopaque; - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; } @@ -933,7 +933,7 @@ hash_xlog_split_cleanup(XLogReaderState *record) page = (Page) BufferGetPage(buffer); - bucket_opaque = (HashPageOpaque) PageGetSpecialPointer(page); + bucket_opaque = HashPageGetOpaque(page); bucket_opaque->hasho_flag &= ~LH_BUCKET_NEEDS_SPLIT_CLEANUP; PageSetLSN(page, lsn); MarkBufferDirty(buffer); @@ -1024,7 +1024,7 @@ hash_xlog_vacuum_one_page(XLogReaderState *record) * Mark the page as not containing any LP_DEAD items. See comments in * _hash_vacuum_one_page() for details. */ - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; PageSetLSN(page, lsn); @@ -1116,7 +1116,7 @@ hash_mask(char *pagedata, BlockNumber blkno) mask_page_hint_bits(page); mask_unused_space(page); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); pagetype = opaque->hasho_flag & LH_PAGE_TYPE; if (pagetype == LH_UNUSED_PAGE) diff --git a/src/backend/access/hash/hashinsert.c b/src/backend/access/hash/hashinsert.c index faf609c157..4f2fecb908 100644 --- a/src/backend/access/hash/hashinsert.c +++ b/src/backend/access/hash/hashinsert.c @@ -95,7 +95,7 @@ restart_insert: bucket_buf = buf; page = BufferGetPage(buf); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); bucket = pageopaque->hasho_bucket; /* @@ -183,7 +183,7 @@ restart_insert: /* should fit now, given test above */ Assert(PageGetFreeSpace(page) >= itemsz); } - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); Assert((pageopaque->hasho_flag & LH_PAGE_TYPE) == LH_OVERFLOW_PAGE); Assert(pageopaque->hasho_bucket == bucket); } @@ -384,7 +384,7 @@ _hash_vacuum_one_page(Relation rel, Relation hrel, Buffer metabuf, Buffer buf) * check it. Remember that LH_PAGE_HAS_DEAD_TUPLES is only a hint * anyway. */ - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES; metap = HashPageGetMeta(BufferGetPage(metabuf)); diff --git a/src/backend/access/hash/hashovfl.c b/src/backend/access/hash/hashovfl.c index 4836875196..e34cfc302d 100644 --- a/src/backend/access/hash/hashovfl.c +++ b/src/backend/access/hash/hashovfl.c @@ -159,7 +159,7 @@ _hash_addovflpage(Relation rel, Buffer metabuf, Buffer buf, bool retain_pin) BlockNumber nextblkno; page = BufferGetPage(buf); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); nextblkno = pageopaque->hasho_nextblkno; if (!BlockNumberIsValid(nextblkno)) @@ -364,7 +364,7 @@ found: /* initialize new overflow page */ ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = BufferGetBlockNumber(buf); ovflopaque->hasho_nextblkno = InvalidBlockNumber; ovflopaque->hasho_bucket = pageopaque->hasho_bucket; @@ -516,7 +516,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, _hash_checkpage(rel, ovflbuf, LH_OVERFLOW_PAGE); ovflblkno = BufferGetBlockNumber(ovflbuf); ovflpage = BufferGetPage(ovflbuf); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); nextblkno = ovflopaque->hasho_nextblkno; prevblkno = ovflopaque->hasho_prevblkno; writeblkno = BufferGetBlockNumber(wbuf); @@ -600,7 +600,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, */ _hash_pageinit(ovflpage, BufferGetPageSize(ovflbuf)); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(ovflpage); + ovflopaque = HashPageGetOpaque(ovflpage); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -613,7 +613,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, if (BufferIsValid(prevbuf)) { Page prevpage = BufferGetPage(prevbuf); - HashPageOpaque prevopaque = (HashPageOpaque) PageGetSpecialPointer(prevpage); + HashPageOpaque prevopaque = HashPageGetOpaque(prevpage); Assert(prevopaque->hasho_bucket == bucket); prevopaque->hasho_nextblkno = nextblkno; @@ -622,7 +622,7 @@ _hash_freeovflpage(Relation rel, Buffer bucketbuf, Buffer ovflbuf, if (BufferIsValid(nextbuf)) { Page nextpage = BufferGetPage(nextbuf); - HashPageOpaque nextopaque = (HashPageOpaque) PageGetSpecialPointer(nextpage); + HashPageOpaque nextopaque = HashPageGetOpaque(nextpage); Assert(nextopaque->hasho_bucket == bucket); nextopaque->hasho_prevblkno = prevblkno; @@ -751,7 +751,7 @@ _hash_initbitmapbuffer(Buffer buf, uint16 bmsize, bool initpage) _hash_pageinit(pg, BufferGetPageSize(buf)); /* initialize the page's special space */ - op = (HashPageOpaque) PageGetSpecialPointer(pg); + op = HashPageGetOpaque(pg); op->hasho_prevblkno = InvalidBlockNumber; op->hasho_nextblkno = InvalidBlockNumber; op->hasho_bucket = InvalidBucket; @@ -824,7 +824,7 @@ _hash_squeezebucket(Relation rel, wblkno = bucket_blkno; wbuf = bucket_buf; wpage = BufferGetPage(wbuf); - wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage); + wopaque = HashPageGetOpaque(wpage); /* * if there aren't any overflow pages, there's nothing to squeeze. caller @@ -855,7 +855,7 @@ _hash_squeezebucket(Relation rel, LH_OVERFLOW_PAGE, bstrategy); rpage = BufferGetPage(rbuf); - ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage); + ropaque = HashPageGetOpaque(rpage); Assert(ropaque->hasho_bucket == bucket); } while (BlockNumberIsValid(ropaque->hasho_nextblkno)); @@ -1005,7 +1005,7 @@ readpage: wbuf = next_wbuf; wpage = BufferGetPage(wbuf); - wopaque = (HashPageOpaque) PageGetSpecialPointer(wpage); + wopaque = HashPageGetOpaque(wpage); Assert(wopaque->hasho_bucket == bucket); retain_pin = false; @@ -1076,7 +1076,7 @@ readpage: LH_OVERFLOW_PAGE, bstrategy); rpage = BufferGetPage(rbuf); - ropaque = (HashPageOpaque) PageGetSpecialPointer(rpage); + ropaque = HashPageGetOpaque(rpage); Assert(ropaque->hasho_bucket == bucket); } diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c index 28c5297a1d..39206d1942 100644 --- a/src/backend/access/hash/hashpage.c +++ b/src/backend/access/hash/hashpage.c @@ -166,7 +166,7 @@ _hash_initbuf(Buffer buf, uint32 max_bucket, uint32 num_bucket, uint32 flag, if (initpage) _hash_pageinit(page, BufferGetPageSize(buf)); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); /* * Set hasho_prevblkno with current hashm_maxbucket. This value will be @@ -529,7 +529,7 @@ _hash_init_metabuffer(Buffer buf, double num_tuples, RegProcedure procid, if (initpage) _hash_pageinit(page, BufferGetPageSize(buf)); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); pageopaque->hasho_prevblkno = InvalidBlockNumber; pageopaque->hasho_nextblkno = InvalidBlockNumber; pageopaque->hasho_bucket = InvalidBucket; @@ -693,7 +693,7 @@ restart_expand: goto fail; opage = BufferGetPage(buf_oblkno); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); /* * We want to finish the split from a bucket as there is no apparent @@ -864,7 +864,7 @@ restart_expand: lowmask = metap->hashm_lowmask; opage = BufferGetPage(buf_oblkno); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); /* * Mark the old bucket to indicate that split is in progress. (At @@ -883,7 +883,7 @@ restart_expand: * initialize the new bucket's primary page and mark it to indicate that * split is in progress. */ - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); nopaque->hasho_prevblkno = maxbucket; nopaque->hasho_nextblkno = InvalidBlockNumber; nopaque->hasho_bucket = new_bucket; @@ -1010,7 +1010,7 @@ _hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks) */ _hash_pageinit(page, BLCKSZ); - ovflopaque = (HashPageOpaque) PageGetSpecialPointer(page); + ovflopaque = HashPageGetOpaque(page); ovflopaque->hasho_prevblkno = InvalidBlockNumber; ovflopaque->hasho_nextblkno = InvalidBlockNumber; @@ -1091,11 +1091,11 @@ _hash_splitbucket(Relation rel, bucket_obuf = obuf; opage = BufferGetPage(obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); bucket_nbuf = nbuf; npage = BufferGetPage(nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); /* Copy the predicate locks from old bucket to new bucket. */ PredicateLockPageSplit(rel, @@ -1198,7 +1198,7 @@ _hash_splitbucket(Relation rel, /* chain to a new overflow page */ nbuf = _hash_addovflpage(rel, metabuf, nbuf, (nbuf == bucket_nbuf)); npage = BufferGetPage(nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); } itups[nitups++] = new_itup; @@ -1251,7 +1251,7 @@ _hash_splitbucket(Relation rel, /* Else, advance to next old page */ obuf = _hash_getbuf(rel, oblkno, HASH_READ, LH_OVERFLOW_PAGE); opage = BufferGetPage(obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); } /* @@ -1264,11 +1264,11 @@ _hash_splitbucket(Relation rel, */ LockBuffer(bucket_obuf, BUFFER_LOCK_EXCLUSIVE); opage = BufferGetPage(bucket_obuf); - oopaque = (HashPageOpaque) PageGetSpecialPointer(opage); + oopaque = HashPageGetOpaque(opage); LockBuffer(bucket_nbuf, BUFFER_LOCK_EXCLUSIVE); npage = BufferGetPage(bucket_nbuf); - nopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + nopaque = HashPageGetOpaque(npage); START_CRIT_SECTION(); @@ -1392,7 +1392,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket, bucket_nbuf = nbuf; npage = BufferGetPage(nbuf); - npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + npageopaque = HashPageGetOpaque(npage); /* Scan each tuple in new page */ nmaxoffnum = PageGetMaxOffsetNumber(npage); @@ -1446,7 +1446,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket, } npage = BufferGetPage(bucket_nbuf); - npageopaque = (HashPageOpaque) PageGetSpecialPointer(npage); + npageopaque = HashPageGetOpaque(npage); nbucket = npageopaque->hasho_bucket; _hash_splitbucket(rel, metabuf, obucket, @@ -1587,7 +1587,7 @@ _hash_getbucketbuf_from_hashkey(Relation rel, uint32 hashkey, int access, /* Fetch the primary bucket page for the bucket */ buf = _hash_getbuf(rel, blkno, access, LH_BUCKET_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); Assert(opaque->hasho_bucket == bucket); Assert(opaque->hasho_prevblkno != InvalidBlockNumber); diff --git a/src/backend/access/hash/hashsearch.c b/src/backend/access/hash/hashsearch.c index 7ca542a3fb..524af27409 100644 --- a/src/backend/access/hash/hashsearch.c +++ b/src/backend/access/hash/hashsearch.c @@ -187,7 +187,7 @@ _hash_readnext(IndexScanDesc scan, { *pagep = BufferGetPage(*bufp); TestForOldSnapshot(scan->xs_snapshot, rel, *pagep); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); } } @@ -233,7 +233,7 @@ _hash_readprev(IndexScanDesc scan, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE); *pagep = BufferGetPage(*bufp); TestForOldSnapshot(scan->xs_snapshot, rel, *pagep); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); /* * We always maintain the pin on bucket page for whole scan operation, @@ -258,7 +258,7 @@ _hash_readprev(IndexScanDesc scan, LockBuffer(*bufp, BUFFER_LOCK_SHARE); *pagep = BufferGetPage(*bufp); - *opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep); + *opaquep = HashPageGetOpaque(*pagep); /* move to the end of bucket chain */ while (BlockNumberIsValid((*opaquep)->hasho_nextblkno)) @@ -352,7 +352,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir) PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot); page = BufferGetPage(buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); bucket = opaque->hasho_bucket; so->hashso_bucket_buf = buf; @@ -398,7 +398,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir) LockBuffer(buf, BUFFER_LOCK_SHARE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); Assert(opaque->hasho_bucket == bucket); if (H_BUCKET_BEING_POPULATED(opaque)) @@ -463,7 +463,7 @@ _hash_readpage(IndexScanDesc scan, Buffer *bufP, ScanDirection dir) Assert(BufferIsValid(buf)); _hash_checkpage(rel, buf, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); so->currPos.buf = buf; so->currPos.currPage = BufferGetBlockNumber(buf); diff --git a/src/backend/access/hash/hashutil.c b/src/backend/access/hash/hashutil.c index edb6fa968f..fe37bc47cb 100644 --- a/src/backend/access/hash/hashutil.c +++ b/src/backend/access/hash/hashutil.c @@ -239,7 +239,7 @@ _hash_checkpage(Relation rel, Buffer buf, int flags) if (flags) { - HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page); + HashPageOpaque opaque = HashPageGetOpaque(page); if ((opaque->hasho_flag & flags) == 0) ereport(ERROR, @@ -574,7 +574,7 @@ _hash_kill_items(IndexScanDesc scan) buf = _hash_getbuf(rel, blkno, HASH_READ, LH_OVERFLOW_PAGE); page = BufferGetPage(buf); - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); for (i = 0; i < numKilled; i++) diff --git a/src/backend/access/nbtree/nbtdedup.c b/src/backend/access/nbtree/nbtdedup.c index 4c48554aec..3e11805293 100644 --- a/src/backend/access/nbtree/nbtdedup.c +++ b/src/backend/access/nbtree/nbtdedup.c @@ -62,7 +62,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem, minoff, maxoff; Page page = BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); Page newpage; BTDedupState state; Size pagesaving = 0; @@ -231,7 +231,7 @@ _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel, IndexTuple newitem, */ if (P_HAS_GARBAGE(opaque)) { - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage); + BTPageOpaque nopaque = BTPageGetOpaque(newpage); nopaque->btpo_flags &= ~BTP_HAS_GARBAGE; } @@ -310,7 +310,7 @@ _bt_bottomupdel_pass(Relation rel, Buffer buf, Relation heapRel, minoff, maxoff; Page page = BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); BTDedupState state; TM_IndexDeleteOp delstate; bool neverdedup; diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c index 68628ec000..f6f4af8bfe 100644 --- a/src/backend/access/nbtree/nbtinsert.c +++ b/src/backend/access/nbtree/nbtinsert.c @@ -329,7 +329,7 @@ _bt_search_insert(Relation rel, BTInsertState insertstate) _bt_checkpage(rel, insertstate->buf); page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Check if the page is still the rightmost leaf page and has @@ -428,7 +428,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel, InitDirtySnapshot(SnapshotDirty); page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); /* @@ -733,7 +733,7 @@ _bt_check_unique(Relation rel, BTInsertState insertstate, Relation heapRel, nbuf = _bt_relandgetbuf(rel, nbuf, nblkno, BT_READ); page = BufferGetPage(nbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_IGNORE(opaque)) break; if (P_RIGHTMOST(opaque)) @@ -822,7 +822,7 @@ _bt_findinsertloc(Relation rel, BTPageOpaque opaque; OffsetNumber newitemoff; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Check 1/3 of a page restriction */ if (unlikely(insertstate->itemsz > BTMaxItemSize(page))) @@ -888,7 +888,7 @@ _bt_findinsertloc(Relation rel, _bt_stepright(rel, insertstate, stack); /* Update local state after stepping right */ page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Assume duplicates (if checkingunique) */ uniquedup = true; } @@ -972,7 +972,7 @@ _bt_findinsertloc(Relation rel, _bt_stepright(rel, insertstate, stack); /* Update local state after stepping right */ page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } } @@ -1030,7 +1030,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack) BlockNumber rblkno; page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); rbuf = InvalidBuffer; rblkno = opaque->btpo_next; @@ -1038,7 +1038,7 @@ _bt_stepright(Relation rel, BTInsertState insertstate, BTStack stack) { rbuf = _bt_relandgetbuf(rel, rbuf, rblkno, BT_WRITE); page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If this page was incompletely split, finish the split now. We do @@ -1120,7 +1120,7 @@ _bt_insertonpg(Relation rel, IndexTuple nposting = NULL; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); isleaf = P_ISLEAF(opaque); isroot = P_ISROOT(opaque); isrightmost = P_RIGHTMOST(opaque); @@ -1296,7 +1296,7 @@ _bt_insertonpg(Relation rel, if (!isleaf) { Page cpage = BufferGetPage(cbuf); - BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage); + BTPageOpaque cpageop = BTPageGetOpaque(cpage); Assert(P_INCOMPLETE_SPLIT(cpageop)); cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; @@ -1504,7 +1504,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, * only workspace. */ origpage = BufferGetPage(buf); - oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + oopaque = BTPageGetOpaque(origpage); isleaf = P_ISLEAF(oopaque); isrightmost = P_RIGHTMOST(oopaque); maxoff = PageGetMaxOffsetNumber(origpage); @@ -1540,7 +1540,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, /* Allocate temp buffer for leftpage */ leftpage = PageGetTempPage(origpage); _bt_pageinit(leftpage, BufferGetPageSize(buf)); - lopaque = (BTPageOpaque) PageGetSpecialPointer(leftpage); + lopaque = BTPageGetOpaque(leftpage); /* * leftpage won't be the root when we're done. Also, clear the SPLIT_END @@ -1716,7 +1716,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, rightpage = BufferGetPage(rbuf); rightpagenumber = BufferGetBlockNumber(rbuf); /* rightpage was initialized by _bt_getbuf */ - ropaque = (BTPageOpaque) PageGetSpecialPointer(rightpage); + ropaque = BTPageGetOpaque(rightpage); /* * Finish off remaining leftpage special area fields. They cannot be set @@ -1887,7 +1887,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, { sbuf = _bt_getbuf(rel, oopaque->btpo_next, BT_WRITE); spage = BufferGetPage(sbuf); - sopaque = (BTPageOpaque) PageGetSpecialPointer(spage); + sopaque = BTPageGetOpaque(spage); if (sopaque->btpo_prev != origpagenumber) { memset(rightpage, 0, BufferGetPageSize(rbuf)); @@ -1952,7 +1952,7 @@ _bt_split(Relation rel, BTScanInsert itup_key, Buffer buf, Buffer cbuf, if (!isleaf) { Page cpage = BufferGetPage(cbuf); - BTPageOpaque cpageop = (BTPageOpaque) PageGetSpecialPointer(cpage); + BTPageOpaque cpageop = BTPageGetOpaque(cpage); cpageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; MarkBufferDirty(cbuf); @@ -2139,7 +2139,7 @@ _bt_insert_parent(Relation rel, BTPageOpaque opaque; elog(DEBUG2, "concurrent ROOT page split"); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * We should never reach here when a leaf page split takes place @@ -2230,7 +2230,7 @@ void _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack) { Page lpage = BufferGetPage(lbuf); - BTPageOpaque lpageop = (BTPageOpaque) PageGetSpecialPointer(lpage); + BTPageOpaque lpageop = BTPageGetOpaque(lpage); Buffer rbuf; Page rpage; BTPageOpaque rpageop; @@ -2242,7 +2242,7 @@ _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack) /* Lock right sibling, the one missing the downlink */ rbuf = _bt_getbuf(rel, lpageop->btpo_next, BT_WRITE); rpage = BufferGetPage(rbuf); - rpageop = (BTPageOpaque) PageGetSpecialPointer(rpage); + rpageop = BTPageGetOpaque(rpage); /* Could this be a root split? */ if (!stack) @@ -2320,7 +2320,7 @@ _bt_getstackbuf(Relation rel, BTStack stack, BlockNumber child) buf = _bt_getbuf(rel, blkno, BT_WRITE); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_INCOMPLETE_SPLIT(opaque)) { @@ -2451,7 +2451,7 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf) lbkno = BufferGetBlockNumber(lbuf); rbkno = BufferGetBlockNumber(rbuf); lpage = BufferGetPage(lbuf); - lopaque = (BTPageOpaque) PageGetSpecialPointer(lpage); + lopaque = BTPageGetOpaque(lpage); /* get a new root page */ rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE); @@ -2492,11 +2492,11 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf) _bt_upgrademetapage(metapg); /* set btree special data */ - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE; rootopaque->btpo_flags = BTP_ROOT; rootopaque->btpo_level = - ((BTPageOpaque) PageGetSpecialPointer(lpage))->btpo_level + 1; + (BTPageGetOpaque(lpage))->btpo_level + 1; rootopaque->btpo_cycleid = 0; /* update metapage data */ @@ -2680,7 +2680,7 @@ _bt_delete_or_dedup_one_page(Relation rel, Relation heapRel, Buffer buffer = insertstate->buf; BTScanInsert itup_key = insertstate->itup_key; Page page = BufferGetPage(buffer); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); Assert(simpleonly || itup_key->heapkeyspace); diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c index 6b5f01e1d0..20adb602a4 100644 --- a/src/backend/access/nbtree/nbtpage.c +++ b/src/backend/access/nbtree/nbtpage.c @@ -85,7 +85,7 @@ _bt_initmetapage(Page page, BlockNumber rootbknum, uint32 level, metad->btm_last_cleanup_num_heap_tuples = -1.0; metad->btm_allequalimage = allequalimage; - metaopaque = (BTPageOpaque) PageGetSpecialPointer(page); + metaopaque = BTPageGetOpaque(page); metaopaque->btpo_flags = BTP_META; /* @@ -112,7 +112,7 @@ _bt_upgrademetapage(Page page) BTPageOpaque metaopaque PG_USED_FOR_ASSERTS_ONLY; metad = BTPageGetMeta(page); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(page); + metaopaque = BTPageGetOpaque(page); /* It must be really a meta page of upgradable version */ Assert(metaopaque->btpo_flags & BTP_META); @@ -148,7 +148,7 @@ _bt_getmeta(Relation rel, Buffer metabuf) BTMetaPageData *metad; metapg = BufferGetPage(metabuf); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg); + metaopaque = BTPageGetOpaque(metapg); metad = BTPageGetMeta(metapg); /* sanity-check the metapage */ @@ -372,7 +372,7 @@ _bt_getroot(Relation rel, int access) rootbuf = _bt_getbuf(rel, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); /* * Since the cache might be stale, we check the page more carefully @@ -440,7 +440,7 @@ _bt_getroot(Relation rel, int access) rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE); rootblkno = BufferGetBlockNumber(rootbuf); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); rootopaque->btpo_prev = rootopaque->btpo_next = P_NONE; rootopaque->btpo_flags = (BTP_LEAF | BTP_ROOT); rootopaque->btpo_level = 0; @@ -534,7 +534,7 @@ _bt_getroot(Relation rel, int access) { rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); if (!P_IGNORE(rootopaque)) break; @@ -598,7 +598,7 @@ _bt_gettrueroot(Relation rel) metabuf = _bt_getbuf(rel, BTREE_METAPAGE, BT_READ); metapg = BufferGetPage(metabuf); - metaopaque = (BTPageOpaque) PageGetSpecialPointer(metapg); + metaopaque = BTPageGetOpaque(metapg); metad = BTPageGetMeta(metapg); if (!P_ISMETA(metaopaque) || @@ -637,7 +637,7 @@ _bt_gettrueroot(Relation rel) { rootbuf = _bt_relandgetbuf(rel, rootbuf, rootblkno, BT_READ); rootpage = BufferGetPage(rootbuf); - rootopaque = (BTPageOpaque) PageGetSpecialPointer(rootpage); + rootopaque = BTPageGetOpaque(rootpage); if (!P_IGNORE(rootopaque)) break; @@ -1220,7 +1220,7 @@ _bt_delitems_vacuum(Relation rel, Buffer buf, * We can clear the vacuum cycle ID since this page has certainly been * processed by the current vacuum scan. */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_cycleid = 0; /* @@ -1338,7 +1338,7 @@ _bt_delitems_delete(Relation rel, Buffer buf, TransactionId latestRemovedXid, * Unlike _bt_delitems_vacuum, we *must not* clear the vacuum cycle ID at * this point. The VACUUM command alone controls vacuum cycle IDs. */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Clear the BTP_HAS_GARBAGE page flag. @@ -1718,7 +1718,7 @@ _bt_leftsib_splitflag(Relation rel, BlockNumber leftsib, BlockNumber target) buf = _bt_getbuf(rel, leftsib, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If the left sibling was concurrently split, so that its next-pointer @@ -1773,7 +1773,7 @@ _bt_rightsib_halfdeadflag(Relation rel, BlockNumber leafrightsib) buf = _bt_getbuf(rel, leafrightsib, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque)); result = P_ISHALFDEAD(opaque); @@ -1842,7 +1842,7 @@ _bt_pagedel(Relation rel, Buffer leafbuf, BTVacState *vstate) for (;;) { page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Internal pages are never deleted directly, only as part of deleting @@ -2099,7 +2099,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) IndexTupleData trunctuple; page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(!P_RIGHTMOST(opaque) && !P_ISROOT(opaque) && P_ISLEAF(opaque) && !P_IGNORE(opaque) && @@ -2154,7 +2154,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * before entering the critical section --- otherwise it'd be a PANIC. */ page = BufferGetPage(subtreeparent); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); #ifdef USE_ASSERT_CHECKING @@ -2201,7 +2201,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * nbtree/README. */ page = BufferGetPage(subtreeparent); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); itemid = PageGetItemId(page, poffset); itup = (IndexTuple) PageGetItem(page, itemid); @@ -2216,7 +2216,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) * is set to InvalidBlockNumber. */ page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags |= BTP_HALF_DEAD; Assert(PageGetMaxOffsetNumber(page) == P_HIKEY); @@ -2253,7 +2253,7 @@ _bt_mark_page_halfdead(Relation rel, Buffer leafbuf, BTStack stack) XLogRegisterBuffer(1, subtreeparent, REGBUF_STANDARD); page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); xlrec.leftblk = opaque->btpo_prev; xlrec.rightblk = opaque->btpo_next; @@ -2325,7 +2325,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, BlockNumber leaftopparent; page = BufferGetPage(leafbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque) && !P_ISDELETED(opaque) && P_ISHALFDEAD(opaque)); @@ -2364,7 +2364,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* Fetch the block number of the target's left sibling */ buf = _bt_getbuf(rel, target, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); leftsib = opaque->btpo_prev; targetlevel = opaque->btpo_level; Assert(targetlevel > 0); @@ -2391,7 +2391,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, { lbuf = _bt_getbuf(rel, leftsib, BT_WRITE); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); while (P_ISDELETED(opaque) || opaque->btpo_next != target) { bool leftsibvalid = true; @@ -2441,7 +2441,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* step right one page */ lbuf = _bt_getbuf(rel, leftsib, BT_WRITE); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } } else @@ -2450,7 +2450,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, /* Next write-lock the target page itself */ _bt_lockbuf(rel, buf, BT_WRITE); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Check page is still empty etc, else abandon deletion. This is just for @@ -2505,7 +2505,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, rightsib = opaque->btpo_next; rbuf = _bt_getbuf(rel, rightsib, BT_WRITE); page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (opaque->btpo_prev != target) ereport(ERROR, (errcode(ERRCODE_INDEX_CORRUPTED), @@ -2528,7 +2528,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, if (leftsib == P_NONE && rightsib_is_rightmost) { page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_RIGHTMOST(opaque)) { /* rightsib will be the only one left on the level */ @@ -2565,12 +2565,12 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, if (BufferIsValid(lbuf)) { page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(opaque->btpo_next == target); opaque->btpo_next = rightsib; } page = BufferGetPage(rbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(opaque->btpo_prev == target); opaque->btpo_prev = leftsib; @@ -2599,7 +2599,7 @@ _bt_unlink_halfdead_page(Relation rel, Buffer leafbuf, BlockNumber scanblkno, * of that scan. */ page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISHALFDEAD(opaque) || !P_ISLEAF(opaque)); /* @@ -2814,7 +2814,7 @@ _bt_lock_subtree_parent(Relation rel, BlockNumber child, BTStack stack, parentoffset = stack->bts_offset; page = BufferGetPage(pbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); maxoff = PageGetMaxOffsetNumber(page); leftsibparent = opaque->btpo_prev; diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c index dacf3f7a58..06131f23d4 100644 --- a/src/backend/access/nbtree/nbtree.c +++ b/src/backend/access/nbtree/nbtree.c @@ -1070,7 +1070,7 @@ backtrack: if (!PageIsNew(page)) { _bt_checkpage(rel, buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } Assert(blkno <= scanblkno); diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c index 9d82d4904d..c74543bfde 100644 --- a/src/backend/access/nbtree/nbtsearch.c +++ b/src/backend/access/nbtree/nbtsearch.c @@ -134,7 +134,7 @@ _bt_search(Relation rel, BTScanInsert key, Buffer *bufP, int access, /* if this is a leaf page, we're done */ page = BufferGetPage(*bufP); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISLEAF(opaque)) break; @@ -268,7 +268,7 @@ _bt_moveright(Relation rel, { page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_RIGHTMOST(opaque)) break; @@ -347,7 +347,7 @@ _bt_binsrch(Relation rel, cmpval; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* Requesting nextkey semantics while using scantid seems nonsensical */ Assert(!key->nextkey || key->scantid == NULL); @@ -451,7 +451,7 @@ _bt_binsrch_insert(Relation rel, BTInsertState insertstate) cmpval; page = BufferGetPage(insertstate->buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); Assert(!key->nextkey); @@ -659,7 +659,7 @@ _bt_compare(Relation rel, OffsetNumber offnum) { TupleDesc itupdesc = RelationGetDescr(rel); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); IndexTuple itup; ItemPointer heapTid; ScanKey scankey; @@ -1536,7 +1536,7 @@ _bt_readpage(IndexScanDesc scan, ScanDirection dir, OffsetNumber offnum) Assert(BufferIsValid(so->currPos.buf)); page = BufferGetPage(so->currPos.buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* allow next page be processed by parallel worker */ if (scan->parallel_scan) @@ -2007,7 +2007,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir) so->currPos.buf = _bt_getbuf(rel, blkno, BT_READ); page = BufferGetPage(so->currPos.buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* check for deleted page */ if (!P_IGNORE(opaque)) { @@ -2110,7 +2110,7 @@ _bt_readnextpage(IndexScanDesc scan, BlockNumber blkno, ScanDirection dir) */ page = BufferGetPage(so->currPos.buf); TestForOldSnapshot(scan->xs_snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_IGNORE(opaque)) { PredicateLockPage(rel, BufferGetBlockNumber(so->currPos.buf), scan->xs_snapshot); @@ -2191,7 +2191,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) BTPageOpaque opaque; page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); for (;;) { @@ -2216,7 +2216,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_getbuf(rel, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * If this isn't the page we want, walk right till we find what we @@ -2243,14 +2243,14 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } /* Return to the original page to see what's up */ buf = _bt_relandgetbuf(rel, buf, obknum, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* @@ -2268,7 +2268,7 @@ _bt_walk_left(Relation rel, Buffer buf, Snapshot snapshot) buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_ISDELETED(opaque)) break; } @@ -2329,7 +2329,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); for (;;) { @@ -2349,7 +2349,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); TestForOldSnapshot(snapshot, rel, page); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } /* Done? */ @@ -2372,7 +2372,7 @@ _bt_get_endpoint(Relation rel, uint32 level, bool rightmost, buf = _bt_relandgetbuf(rel, buf, blkno, BT_READ); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); } return buf; @@ -2418,7 +2418,7 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) PredicateLockPage(rel, BufferGetBlockNumber(buf), scan->xs_snapshot); page = BufferGetPage(buf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); Assert(P_ISLEAF(opaque)); if (ScanDirectionIsForward(dir)) diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index 8a19de2f66..c074513efa 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -625,7 +625,7 @@ _bt_blnewpage(uint32 level) _bt_pageinit(page, BLCKSZ); /* Initialize BT opaque state */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_prev = opaque->btpo_next = P_NONE; opaque->btpo_level = level; opaque->btpo_flags = (level > 0) ? 0 : BTP_LEAF; @@ -1000,9 +1000,9 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup, Assert((BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) <= IndexRelationGetNumberOfKeyAttributes(wstate->index) && BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) > 0) || - P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage))); + P_LEFTMOST(BTPageGetOpaque(opage))); Assert(BTreeTupleGetNAtts(state->btps_lowkey, wstate->index) == 0 || - !P_LEFTMOST((BTPageOpaque) PageGetSpecialPointer(opage))); + !P_LEFTMOST(BTPageGetOpaque(opage))); BTreeTupleSetDownLink(state->btps_lowkey, oblkno); _bt_buildadd(wstate, state->btps_next, state->btps_lowkey, 0); pfree(state->btps_lowkey); @@ -1017,8 +1017,8 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup, * Set the sibling links for both pages. */ { - BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(opage); - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(npage); + BTPageOpaque oopaque = BTPageGetOpaque(opage); + BTPageOpaque nopaque = BTPageGetOpaque(npage); oopaque->btpo_next = nblkno; nopaque->btpo_prev = oblkno; @@ -1125,7 +1125,7 @@ _bt_uppershutdown(BTWriteState *wstate, BTPageState *state) BTPageOpaque opaque; blkno = s->btps_blkno; - opaque = (BTPageOpaque) PageGetSpecialPointer(s->btps_page); + opaque = BTPageGetOpaque(s->btps_page); /* * We have to link the last page on this level to somewhere. diff --git a/src/backend/access/nbtree/nbtsplitloc.c b/src/backend/access/nbtree/nbtsplitloc.c index c46594e1a2..ee01ceafda 100644 --- a/src/backend/access/nbtree/nbtsplitloc.c +++ b/src/backend/access/nbtree/nbtsplitloc.c @@ -152,7 +152,7 @@ _bt_findsplitloc(Relation rel, SplitPoint leftpage, rightpage; - opaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + opaque = BTPageGetOpaque(origpage); maxoff = PageGetMaxOffsetNumber(origpage); /* Total free space available on a btree page, after fixed overhead */ diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c index 84164748b3..96c72fc432 100644 --- a/src/backend/access/nbtree/nbtutils.c +++ b/src/backend/access/nbtree/nbtutils.c @@ -1774,7 +1774,7 @@ _bt_killitems(IndexScanDesc scan) } } - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); minoff = P_FIRSTDATAKEY(opaque); maxoff = PageGetMaxOffsetNumber(page); @@ -2474,7 +2474,7 @@ _bt_check_natts(Relation rel, bool heapkeyspace, Page page, OffsetNumber offnum) { int16 natts = IndexRelationGetNumberOfAttributes(rel); int16 nkeyatts = IndexRelationGetNumberOfKeyAttributes(rel); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); IndexTuple itup; int tupnatts; @@ -2662,7 +2662,7 @@ _bt_check_third_page(Relation rel, Relation heap, bool needheaptidspace, * Internal page insertions cannot fail here, because that would mean that * an earlier leaf level insertion that should have failed didn't */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (!P_ISLEAF(opaque)) elog(ERROR, "cannot insert oversized tuple of size %zu on internal page of index \"%s\"", itemsz, RelationGetRelationName(rel)); diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c index 611f412ba8..fba124b940 100644 --- a/src/backend/access/nbtree/nbtxlog.c +++ b/src/backend/access/nbtree/nbtxlog.c @@ -115,7 +115,7 @@ _bt_restore_meta(XLogReaderState *record, uint8 block_id) md->btm_last_cleanup_num_heap_tuples = -1.0; md->btm_allequalimage = xlrec->allequalimage; - pageop = (BTPageOpaque) PageGetSpecialPointer(metapg); + pageop = BTPageGetOpaque(metapg); pageop->btpo_flags = BTP_META; /* @@ -146,7 +146,7 @@ _bt_clear_incomplete_split(XLogReaderState *record, uint8 block_id) if (XLogReadBufferForRedo(record, block_id, &buf) == BLK_NEEDS_REDO) { Page page = (Page) BufferGetPage(buf); - BTPageOpaque pageop = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque pageop = BTPageGetOpaque(page); Assert(P_INCOMPLETE_SPLIT(pageop)); pageop->btpo_flags &= ~BTP_INCOMPLETE_SPLIT; @@ -292,7 +292,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) rpage = (Page) BufferGetPage(rbuf); _bt_pageinit(rpage, BufferGetPageSize(rbuf)); - ropaque = (BTPageOpaque) PageGetSpecialPointer(rpage); + ropaque = BTPageGetOpaque(rpage); ropaque->btpo_prev = origpagenumber; ropaque->btpo_next = spagenumber; @@ -317,7 +317,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) * same for the right page. */ Page origpage = (Page) BufferGetPage(buf); - BTPageOpaque oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage); + BTPageOpaque oopaque = BTPageGetOpaque(origpage); OffsetNumber off; IndexTuple newitem = NULL, left_hikey = NULL, @@ -442,7 +442,7 @@ btree_xlog_split(bool newitemonleft, XLogReaderState *record) if (XLogReadBufferForRedo(record, 2, &sbuf) == BLK_NEEDS_REDO) { Page spage = (Page) BufferGetPage(sbuf); - BTPageOpaque spageop = (BTPageOpaque) PageGetSpecialPointer(spage); + BTPageOpaque spageop = BTPageGetOpaque(spage); spageop->btpo_prev = rightpagenumber; @@ -473,7 +473,7 @@ btree_xlog_dedup(XLogReaderState *record) { char *ptr = XLogRecGetBlockData(record, 0, NULL); Page page = (Page) BufferGetPage(buf); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); OffsetNumber offnum, minoff, maxoff; @@ -541,7 +541,7 @@ btree_xlog_dedup(XLogReaderState *record) if (P_HAS_GARBAGE(opaque)) { - BTPageOpaque nopaque = (BTPageOpaque) PageGetSpecialPointer(newpage); + BTPageOpaque nopaque = BTPageGetOpaque(newpage); nopaque->btpo_flags &= ~BTP_HAS_GARBAGE; } @@ -639,7 +639,7 @@ btree_xlog_vacuum(XLogReaderState *record) * Mark the page as not containing any LP_DEAD items --- see comments * in _bt_delitems_vacuum(). */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags &= ~BTP_HAS_GARBAGE; PageSetLSN(page, lsn); @@ -699,7 +699,7 @@ btree_xlog_delete(XLogReaderState *record) PageIndexMultiDelete(page, (OffsetNumber *) ptr, xlrec->ndeleted); /* Mark the page as not containing any LP_DEAD items */ - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); opaque->btpo_flags &= ~BTP_HAS_GARBAGE; PageSetLSN(page, lsn); @@ -737,7 +737,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record) BlockNumber rightsib; page = (Page) BufferGetPage(buffer); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); poffset = xlrec->poffset; @@ -768,7 +768,7 @@ btree_xlog_mark_page_halfdead(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(buffer); _bt_pageinit(page, BufferGetPageSize(buffer)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = xlrec->leftblk; pageop->btpo_next = xlrec->rightblk; @@ -833,7 +833,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) if (XLogReadBufferForRedo(record, 1, &leftbuf) == BLK_NEEDS_REDO) { page = (Page) BufferGetPage(leftbuf); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_next = rightsib; PageSetLSN(page, lsn); @@ -848,7 +848,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(target); _bt_pageinit(page, BufferGetPageSize(target)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = leftsib; pageop->btpo_next = rightsib; @@ -865,7 +865,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) if (XLogReadBufferForRedo(record, 2, &rightbuf) == BLK_NEEDS_REDO) { page = (Page) BufferGetPage(rightbuf); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_prev = leftsib; PageSetLSN(page, lsn); @@ -906,7 +906,7 @@ btree_xlog_unlink_page(uint8 info, XLogReaderState *record) page = (Page) BufferGetPage(leafbuf); _bt_pageinit(page, BufferGetPageSize(leafbuf)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_flags = BTP_HALF_DEAD | BTP_LEAF; pageop->btpo_prev = xlrec->leafleftsib; @@ -948,7 +948,7 @@ btree_xlog_newroot(XLogReaderState *record) page = (Page) BufferGetPage(buffer); _bt_pageinit(page, BufferGetPageSize(buffer)); - pageop = (BTPageOpaque) PageGetSpecialPointer(page); + pageop = BTPageGetOpaque(page); pageop->btpo_flags = BTP_ROOT; pageop->btpo_prev = pageop->btpo_next = P_NONE; @@ -1097,7 +1097,7 @@ btree_mask(char *pagedata, BlockNumber blkno) mask_page_hint_bits(page); mask_unused_space(page); - maskopaq = (BTPageOpaque) PageGetSpecialPointer(page); + maskopaq = BTPageGetOpaque(page); if (P_ISLEAF(maskopaq)) { diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c index d2510ee648..70278c4f93 100644 --- a/contrib/amcheck/verify_nbtree.c +++ b/contrib/amcheck/verify_nbtree.c @@ -691,7 +691,7 @@ bt_check_level_from_leftmost(BtreeCheckState *state, BtreeLevel level) state->target = palloc_btree_page(state, state->targetblock); state->targetlsn = PageGetLSN(state->target); - opaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + opaque = BTPageGetOpaque(state->target); if (P_IGNORE(opaque)) { @@ -927,7 +927,7 @@ bt_recheck_sibling_links(BtreeCheckState *state, LockBuffer(lbuf, BT_READ); _bt_checkpage(state->rel, lbuf); page = BufferGetPage(lbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISDELETED(opaque)) { /* @@ -951,7 +951,7 @@ bt_recheck_sibling_links(BtreeCheckState *state, LockBuffer(newtargetbuf, BT_READ); _bt_checkpage(state->rel, newtargetbuf); page = BufferGetPage(newtargetbuf); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* btpo_prev_from_target may have changed; update it */ btpo_prev_from_target = opaque->btpo_prev; } @@ -1049,7 +1049,7 @@ bt_target_page_check(BtreeCheckState *state) OffsetNumber max; BTPageOpaque topaque; - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); max = PageGetMaxOffsetNumber(state->target); elog(DEBUG2, "verifying %u items on %s block %u", max, @@ -1478,7 +1478,7 @@ bt_target_page_check(BtreeCheckState *state) /* Get fresh copy of target page */ state->target = palloc_btree_page(state, state->targetblock); /* Note that we deliberately do not update target LSN */ - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); /* * All !readonly checks now performed; just return @@ -1552,7 +1552,7 @@ bt_right_page_check_scankey(BtreeCheckState *state) OffsetNumber nline; /* Determine target's next block number */ - opaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + opaque = BTPageGetOpaque(state->target); /* If target is already rightmost, no right sibling; nothing to do here */ if (P_RIGHTMOST(opaque)) @@ -1588,7 +1588,7 @@ bt_right_page_check_scankey(BtreeCheckState *state) CHECK_FOR_INTERRUPTS(); rightpage = palloc_btree_page(state, targetnext); - opaque = (BTPageOpaque) PageGetSpecialPointer(rightpage); + opaque = BTPageGetOpaque(rightpage); if (!P_IGNORE(opaque) || P_RIGHTMOST(opaque)) break; @@ -1893,7 +1893,7 @@ bt_child_highkey_check(BtreeCheckState *state, else page = palloc_btree_page(state, blkno); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* The first page we visit at the level should be leftmost */ if (first && !BlockNumberIsValid(state->prevrightlink) && !P_LEFTMOST(opaque)) @@ -1971,7 +1971,7 @@ bt_child_highkey_check(BtreeCheckState *state, else pivotkey_offset = target_downlinkoffnum; - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); if (!offset_is_negative_infinity(topaque, pivotkey_offset)) { @@ -2128,9 +2128,9 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey, * Check all items, rather than checking just the first and trusting that * the operator class obeys the transitive law. */ - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); child = palloc_btree_page(state, childblock); - copaque = (BTPageOpaque) PageGetSpecialPointer(child); + copaque = BTPageGetOpaque(child); maxoffset = PageGetMaxOffsetNumber(child); /* @@ -2235,7 +2235,7 @@ static void bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit, BlockNumber blkno, Page page) { - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); ItemId itemid; IndexTuple itup; Page child; @@ -2319,7 +2319,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit, CHECK_FOR_INTERRUPTS(); child = palloc_btree_page(state, childblk); - copaque = (BTPageOpaque) PageGetSpecialPointer(child); + copaque = BTPageGetOpaque(child); if (P_ISLEAF(copaque)) break; @@ -2780,7 +2780,7 @@ invariant_l_offset(BtreeCheckState *state, BTScanInsert key, bool nonpivot; ritup = (IndexTuple) PageGetItem(state->target, itemid); - topaque = (BTPageOpaque) PageGetSpecialPointer(state->target); + topaque = BTPageGetOpaque(state->target); nonpivot = P_ISLEAF(topaque) && upperbound >= P_FIRSTDATAKEY(topaque); /* Get number of keys + heap TID for item to the right */ @@ -2895,7 +2895,7 @@ invariant_l_nontarget_offset(BtreeCheckState *state, BTScanInsert key, bool nonpivot; child = (IndexTuple) PageGetItem(nontarget, itemid); - copaque = (BTPageOpaque) PageGetSpecialPointer(nontarget); + copaque = BTPageGetOpaque(nontarget); nonpivot = P_ISLEAF(copaque) && upperbound >= P_FIRSTDATAKEY(copaque); /* Get number of keys + heap TID for child/non-target item */ @@ -2954,7 +2954,7 @@ palloc_btree_page(BtreeCheckState *state, BlockNumber blocknum) memcpy(page, BufferGetPage(buffer), BLCKSZ); UnlockReleaseBuffer(buffer); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_ISMETA(opaque) && blocknum != BTREE_METAPAGE) ereport(ERROR, diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c index 7651c59bbf..3daa31c84d 100644 --- a/contrib/pageinspect/btreefuncs.c +++ b/contrib/pageinspect/btreefuncs.c @@ -93,7 +93,7 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat) Page page = BufferGetPage(buffer); PageHeader phdr = (PageHeader) page; OffsetNumber maxoff = PageGetMaxOffsetNumber(page); - BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); + BTPageOpaque opaque = BTPageGetOpaque(page); int item_size = 0; int off; @@ -525,7 +525,7 @@ bt_page_items_internal(PG_FUNCTION_ARGS, enum pageinspect_version ext_version) uargs->offset = FirstOffsetNumber; - opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page); + opaque = BTPageGetOpaque(uargs->page); if (!P_ISDELETED(opaque)) fctx->max_calls = PageGetMaxOffsetNumber(uargs->page); @@ -622,7 +622,7 @@ bt_page_items_bytea(PG_FUNCTION_ARGS) (int) MAXALIGN(sizeof(BTPageOpaqueData)), (int) PageGetSpecialSize(uargs->page)))); - opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page); + opaque = BTPageGetOpaque(uargs->page); if (P_ISMETA(opaque)) ereport(ERROR, diff --git a/contrib/pageinspect/hashfuncs.c b/contrib/pageinspect/hashfuncs.c index 6de21d6608..69af7b962f 100644 --- a/contrib/pageinspect/hashfuncs.c +++ b/contrib/pageinspect/hashfuncs.c @@ -72,7 +72,7 @@ verify_hash_page(bytea *raw_page, int flags) (int) MAXALIGN(sizeof(HashPageOpaqueData)), (int) PageGetSpecialSize(page)))); - pageopaque = (HashPageOpaque) PageGetSpecialPointer(page); + pageopaque = HashPageGetOpaque(page); if (pageopaque->hasho_page_id != HASHO_PAGE_ID) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), @@ -154,7 +154,7 @@ static void GetHashPageStatistics(Page page, HashPageStat *stat) { OffsetNumber maxoff = PageGetMaxOffsetNumber(page); - HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page); + HashPageOpaque opaque = HashPageGetOpaque(page); int off; stat->dead_items = stat->live_items = 0; @@ -206,7 +206,7 @@ hash_page_type(PG_FUNCTION_ARGS) type = "unused"; else { - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); /* page type (flags) */ pagetype = opaque->hasho_flag & LH_PAGE_TYPE; diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c index 6c4b053dd0..e1048e47ff 100644 --- a/contrib/pgstattuple/pgstatindex.c +++ b/contrib/pgstattuple/pgstatindex.c @@ -281,7 +281,7 @@ pgstatindex_impl(Relation rel, FunctionCallInfo fcinfo) LockBuffer(buffer, BUFFER_LOCK_SHARE); page = BufferGetPage(buffer); - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); /* * Determine page type, and update totals. @@ -641,7 +641,7 @@ pgstathashindex(PG_FUNCTION_ARGS) HashPageOpaque opaque; int pagetype; - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); pagetype = opaque->hasho_flag & LH_PAGE_TYPE; if (pagetype == LH_BUCKET_PAGE) diff --git a/contrib/pgstattuple/pgstattuple.c b/contrib/pgstattuple/pgstattuple.c index c9b8f01f9b..3094566908 100644 --- a/contrib/pgstattuple/pgstattuple.c +++ b/contrib/pgstattuple/pgstattuple.c @@ -415,7 +415,7 @@ pgstat_btree_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno, { BTPageOpaque opaque; - opaque = (BTPageOpaque) PageGetSpecialPointer(page); + opaque = BTPageGetOpaque(page); if (P_IGNORE(opaque)) { /* deleted or half-dead page */ @@ -452,7 +452,7 @@ pgstat_hash_page(pgstattuple_type *stat, Relation rel, BlockNumber blkno, { HashPageOpaque opaque; - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + opaque = HashPageGetOpaque(page); switch (opaque->hasho_flag & LH_PAGE_TYPE) { case LH_UNUSED_PAGE: -- 2.35.1 [application/pgp-signature] signature.asc (833B, ../../[email protected]/3-signature.asc) download ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-03-31 10:09 Matthias van de Meent <[email protected]> parent: Michael Paquier <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Matthias van de Meent @ 2022-03-31 10:09 UTC (permalink / raw) To: Michael Paquier <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; pgsql-hackers On Thu, 31 Mar 2022 at 09:32, Michael Paquier <[email protected]> wrote: > > On Mon, Mar 28, 2022 at 05:09:10PM +0200, Matthias van de Meent wrote: > > Not all clusters have checksums enabled (boo!, but we can't > > realistically fix that), so on-disk corruption could reasonably > > propagate to the rest of such system. Additionally, checksums are only > > checked on read, and updated when the page is written to disk (in > > PageSetChecksumCopy called from FlushBuffer), but this does not check > > for signs of page corruption. As such, a memory bug resulting in > > in-memory corruption of pd_special would persist and would currently > > have the potential to further corrupt neighbouring buffers. > > Well, if it comes to corruption then pd_special is not the only > problem, just one part of it. A broken pd_lower or pd_lower or even > pd_lsn could also cause AMs to point at areas they should not. There > are many reasons that could make things go wrong depending on the > compiled page size. > > >>> A second reason would be less indirection to get to the opaque > >>> pointer. This should improve performance a bit in those cases where we > >>> (initially) only want to access the [Index]PageOpaque struct. > >> > >> We don't have many cases that do that, do we? > > > > Indeed not many, but I know that at least the nbtree-code has some > > cases where it uses the opaque before other fields in the header are > > accessed (sometimes even without accessing the header for other > > reasons): in _bt_moveright and _bt_walk_left. There might be more; but > > these are cases I know of. > > Even these are marginal as the page is already loaded in the shared > buffers.. I can't really disagree there. > While looking at the page, the pieces in 0002 and 0003 that I really > liked are the introduction of the macros to grab the special area for > btree and hash. This brings the code of those APIs closer to GiST, > SpGiST and GIN. And it is possible to move to a possible change in > the checks and/or the shape of all the *GetOpaque macros at once after > the switch to this part is done. So I don't really mind introducing > this part. > > PageGetSpecialOpaque() would not have saved the day with the recent > pageinspect changes, and that's just moving the responsability of the > page header to something else. I am not sure if it is a good idea to > have a mention of the opaque page type in bufpage.h actually, as this > is optional. Having an AssertMacro() checking that pd_special is in > line with MAXALIGN(sizeof(OpaqueData)) is attractive, but I'd rather > keep that in each AM's headers per its optional nature, and an index > AM may handle things differently depending on a page type, as well. PageInit MAXALIGNs the size of the special area that it receives as an argument; so any changes to the page header that would misalign the value would be AM-specific; in which case it is quite unlikely that this is the right accessor for your page's special area. - Matthias ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-01 05:38 Michael Paquier <[email protected]> parent: Matthias van de Meent <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Michael Paquier @ 2022-04-01 05:38 UTC (permalink / raw) To: Matthias van de Meent <[email protected]>; +Cc: pgsql-hackers On Thu, Mar 31, 2022 at 12:09:35PM +0200, Matthias van de Meent wrote: > PageInit MAXALIGNs the size of the special area that it receives as an > argument; so any changes to the page header that would misalign the > value would be AM-specific; in which case it is quite unlikely that > this is the right accessor for your page's special area. Right. I'd still be tempted to keep that per-AM rather than making the checks deeper with one extra macro layer in the page header or with a different macro that would depend on the opaque type, though. Like in the attached, for example. -- Michael Attachments: [text/x-diff] opaque-macros.patch (3.5K, ../../[email protected]/2-opaque-macros.patch) download | inline diff: diff --git a/src/include/access/ginblock.h b/src/include/access/ginblock.h index 9347f464f3..050fff80dc 100644 --- a/src/include/access/ginblock.h +++ b/src/include/access/ginblock.h @@ -108,7 +108,11 @@ typedef struct GinMetaPageData /* * Macros for accessing a GIN index page's opaque data */ -#define GinPageGetOpaque(page) ( (GinPageOpaque) PageGetSpecialPointer(page) ) +#define GinPageGetOpaque(page) \ +( \ + AssertMacro(PageGetSpecialSize(page) == MAXALIGN(sizeof(GinPageOpaqueData))), \ + (GinPageOpaque) PageGetSpecialPointer(page) \ +) #define GinPageIsLeaf(page) ( (GinPageGetOpaque(page)->flags & GIN_LEAF) != 0 ) #define GinPageSetLeaf(page) ( GinPageGetOpaque(page)->flags |= GIN_LEAF ) diff --git a/src/include/access/gist.h b/src/include/access/gist.h index a3337627b8..a10caf8ae9 100644 --- a/src/include/access/gist.h +++ b/src/include/access/gist.h @@ -164,7 +164,11 @@ typedef struct GISTENTRY bool leafkey; } GISTENTRY; -#define GistPageGetOpaque(page) ( (GISTPageOpaque) PageGetSpecialPointer(page) ) +#define GistPageGetOpaque(page) \ +( \ + AssertMacro(PageGetSpecialSize(page) == MAXALIGN(sizeof(GISTPageOpaqueData))), \ + (GISTPageOpaque) PageGetSpecialPointer(page) \ +) #define GistPageIsLeaf(page) ( GistPageGetOpaque(page)->flags & F_LEAF) #define GIST_LEAF(entry) (GistPageIsLeaf((entry)->page)) diff --git a/src/include/access/hash.h b/src/include/access/hash.h index da372841c4..b442ddc4c8 100644 --- a/src/include/access/hash.h +++ b/src/include/access/hash.h @@ -85,7 +85,11 @@ typedef struct HashPageOpaqueData typedef HashPageOpaqueData *HashPageOpaque; -#define HashPageGetOpaque(page) ((HashPageOpaque) PageGetSpecialPointer(page)) +#define HashPageGetOpaque(page) \ +( \ + AssertMacro(PageGetSpecialSize(page) == MAXALIGN(sizeof(HashPageOpaqueData))), \ + (HashPageOpaque) PageGetSpecialPointer(page) \ +) #define H_NEEDS_SPLIT_CLEANUP(opaque) (((opaque)->hasho_flag & LH_BUCKET_NEEDS_SPLIT_CLEANUP) != 0) #define H_BUCKET_BEING_SPLIT(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_SPLIT) != 0) diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h index 93f8267b48..e11839857d 100644 --- a/src/include/access/nbtree.h +++ b/src/include/access/nbtree.h @@ -70,7 +70,11 @@ typedef struct BTPageOpaqueData typedef BTPageOpaqueData *BTPageOpaque; -#define BTPageGetOpaque(page) ((BTPageOpaque) PageGetSpecialPointer(page)) +#define BTPageGetOpaque(page) \ +( \ + AssertMacro(PageGetSpecialSize(page) == MAXALIGN(sizeof(BTPageOpaqueData))), \ + (BTPageOpaque) PageGetSpecialPointer(page) \ +) /* Bits defined in btpo_flags */ #define BTP_LEAF (1 << 0) /* leaf page, i.e. not internal page */ diff --git a/src/include/access/spgist_private.h b/src/include/access/spgist_private.h index eb56b1c6b8..d61433b5af 100644 --- a/src/include/access/spgist_private.h +++ b/src/include/access/spgist_private.h @@ -75,7 +75,12 @@ typedef SpGistPageOpaqueData *SpGistPageOpaque; #define SPGIST_LEAF (1<<2) #define SPGIST_NULLS (1<<3) -#define SpGistPageGetOpaque(page) ((SpGistPageOpaque) PageGetSpecialPointer(page)) +#define SpGistPageGetOpaque(page) \ +( \ + AssertMacro(PageGetSpecialSize(page) == MAXALIGN(sizeof(SpGistPageOpaqueData))), \ + (SpGistPageOpaque) PageGetSpecialPointer(page) \ +) + #define SpGistPageIsMeta(page) (SpGistPageGetOpaque(page)->flags & SPGIST_META) #define SpGistPageIsDeleted(page) (SpGistPageGetOpaque(page)->flags & SPGIST_DELETED) #define SpGistPageIsLeaf(page) (SpGistPageGetOpaque(page)->flags & SPGIST_LEAF) [application/pgp-signature] signature.asc (833B, ../../[email protected]/3-signature.asc) download ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-01 08:50 Matthias van de Meent <[email protected]> parent: Michael Paquier <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Matthias van de Meent @ 2022-04-01 08:50 UTC (permalink / raw) To: Michael Paquier <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; pgsql-hackers On Fri, 1 Apr 2022 at 07:38, Michael Paquier <[email protected]> wrote: > > On Thu, Mar 31, 2022 at 12:09:35PM +0200, Matthias van de Meent wrote: > > PageInit MAXALIGNs the size of the special area that it receives as an > > argument; so any changes to the page header that would misalign the > > value would be AM-specific; in which case it is quite unlikely that > > this is the right accessor for your page's special area. > > Right. I'd still be tempted to keep that per-AM rather than making > the checks deeper with one extra macro layer in the page header or > with a different macro that would depend on the opaque type, though. > Like in the attached, for example. I see. I still would like it better if the access could use this statically determined offset: your opaque-macros.patch doesn't fix the out-of-bound read/write scenariofor non-assert builds, nor does it remove the unneeded indirection through the page header that I was trying to remove. Even in assert-enabled builds; with my proposed changes the code paths for checking the header value and the use of the special area can be executed independently, which allows for parallel (pre-)fetching of the page header and special area, as opposed to the current sequential load order due to the required use of pd_special. -Matthias ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-01 15:12 Matthias van de Meent <[email protected]> parent: Matthias van de Meent <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Matthias van de Meent @ 2022-04-01 15:12 UTC (permalink / raw) To: Michael Paquier <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; pgsql-hackers On Fri, 1 Apr 2022 at 10:50, Matthias van de Meent <[email protected]> wrote: > > On Fri, 1 Apr 2022 at 07:38, Michael Paquier <[email protected]> wrote: > > > > On Thu, Mar 31, 2022 at 12:09:35PM +0200, Matthias van de Meent wrote: > > > PageInit MAXALIGNs the size of the special area that it receives as an > > > argument; so any changes to the page header that would misalign the > > > value would be AM-specific; in which case it is quite unlikely that > > > this is the right accessor for your page's special area. > > > > Right. I'd still be tempted to keep that per-AM rather than making > > the checks deeper with one extra macro layer in the page header or > > with a different macro that would depend on the opaque type, though. > > Like in the attached, for example. I noticed that you committed the equivalent of 0002 and 0003, thank you. Here's a new 0001 to keep CFBot happy. > I see. I still would like it better if the access could use this > statically determined offset: your opaque-macros.patch doesn't fix the > out-of-bound read/write scenariofor non-assert builds, nor does it > remove the unneeded indirection through the page header that I was > trying to remove. > > Even in assert-enabled builds; with my proposed changes the code paths > for checking the header value and the use of the special area can be > executed independently, which allows for parallel (pre-)fetching of > the page header and special area, as opposed to the current sequential > load order due to the required use of pd_special. As an extra argument for this; it removes the need for a temporary variable on the stack; as now all accesses into the special area can be based on offsets off the base page pointer (which is also used often). This would allow the compiler to utilize the available registers more effectively. -Matthias PS. I noticed that between PageGetSpecialPointer and PageGetSpecialOpaque the binary size was bigger by ~1kb for the *Opaque variant when compiled with `CFLAGS="-o2" ./configure --enable-debug`; but that varied a lot between builds and likely related to binary layouts. For similar builds with `--enable-cassert`, the *Opaque build was slimmer by ~ 50kB, which is a suprisingly large amount. Attachments: [application/x-patch] v3-0001-Add-known-size-pre-aligned-special-area-pointer-m.patch (5.3K, ../../CAEze2Wj9c0abW2aRbC8JzOuUdGurO5av6SJ2H83du6tM+Q1rHQ@mail.gmail.com/2-v3-0001-Add-known-size-pre-aligned-special-area-pointer-m.patch) download | inline diff: From d9e6afdfbc021a699e68529cf37d66b8ff999dbc Mon Sep 17 00:00:00 2001 From: Matthias van de Meent <[email protected]> Date: Mon, 28 Mar 2022 14:53:43 +0200 Subject: [PATCH v3] Add known-size pre-aligned special area pointer macro This removes 1 layer of indirection for special areas of which we know the type (=size) and location. Special area access through the page header is an extra cache line that needs to be fetched. If might only want to look at the special area, it is much less effort to calculate the offset to the special area directly instead of first checking the page header - saving one cache line to fetch. Assertions are added to check that the page has a correctly sized special area, and that the page is of the expected size. This detects data corruption, instead of doing random reads/writes into the page or data allocated next to the page being accessed. Additionally, updates the GIN, [SP-]GIST, Hash, and BTree [Index]PageGetOpaque macros with the new pre-aligned special area accessor. --- src/include/access/ginblock.h | 3 ++- src/include/access/gist.h | 3 ++- src/include/access/hash.h | 3 ++- src/include/access/nbtree.h | 3 ++- src/include/access/spgist_private.h | 3 ++- src/include/storage/bufpage.h | 14 ++++++++++++++ 6 files changed, 24 insertions(+), 5 deletions(-) diff --git a/src/include/access/ginblock.h b/src/include/access/ginblock.h index 9347f464f3..3680098c98 100644 --- a/src/include/access/ginblock.h +++ b/src/include/access/ginblock.h @@ -108,7 +108,8 @@ typedef struct GinMetaPageData /* * Macros for accessing a GIN index page's opaque data */ -#define GinPageGetOpaque(page) ( (GinPageOpaque) PageGetSpecialPointer(page) ) +#define GinPageGetOpaque(page) \ + ((GinPageOpaque) PageGetSpecialOpaque(page, GinPageOpaqueData)) #define GinPageIsLeaf(page) ( (GinPageGetOpaque(page)->flags & GIN_LEAF) != 0 ) #define GinPageSetLeaf(page) ( GinPageGetOpaque(page)->flags |= GIN_LEAF ) diff --git a/src/include/access/gist.h b/src/include/access/gist.h index a3337627b8..51223e9051 100644 --- a/src/include/access/gist.h +++ b/src/include/access/gist.h @@ -164,7 +164,8 @@ typedef struct GISTENTRY bool leafkey; } GISTENTRY; -#define GistPageGetOpaque(page) ( (GISTPageOpaque) PageGetSpecialPointer(page) ) +#define GistPageGetOpaque(page) \ + ((GISTPageOpaque) PageGetSpecialOpaque(page, GISTPageOpaqueData)) #define GistPageIsLeaf(page) ( GistPageGetOpaque(page)->flags & F_LEAF) #define GIST_LEAF(entry) (GistPageIsLeaf((entry)->page)) diff --git a/src/include/access/hash.h b/src/include/access/hash.h index da372841c4..0ed6ccc40b 100644 --- a/src/include/access/hash.h +++ b/src/include/access/hash.h @@ -85,7 +85,8 @@ typedef struct HashPageOpaqueData typedef HashPageOpaqueData *HashPageOpaque; -#define HashPageGetOpaque(page) ((HashPageOpaque) PageGetSpecialPointer(page)) +#define HashPageGetOpaque(page) \ + ((HashPageOpaque) PageGetSpecialOpaque(page, HashPageOpaqueData)) #define H_NEEDS_SPLIT_CLEANUP(opaque) (((opaque)->hasho_flag & LH_BUCKET_NEEDS_SPLIT_CLEANUP) != 0) #define H_BUCKET_BEING_SPLIT(opaque) (((opaque)->hasho_flag & LH_BUCKET_BEING_SPLIT) != 0) diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h index 93f8267b48..2d87c8a90f 100644 --- a/src/include/access/nbtree.h +++ b/src/include/access/nbtree.h @@ -70,7 +70,8 @@ typedef struct BTPageOpaqueData typedef BTPageOpaqueData *BTPageOpaque; -#define BTPageGetOpaque(page) ((BTPageOpaque) PageGetSpecialPointer(page)) +#define BTPageGetOpaque(page) \ + ((BTPageOpaque) PageGetSpecialOpaque(page, BTPageOpaqueData)) /* Bits defined in btpo_flags */ #define BTP_LEAF (1 << 0) /* leaf page, i.e. not internal page */ diff --git a/src/include/access/spgist_private.h b/src/include/access/spgist_private.h index eb56b1c6b8..b0bdc7df3e 100644 --- a/src/include/access/spgist_private.h +++ b/src/include/access/spgist_private.h @@ -75,7 +75,8 @@ typedef SpGistPageOpaqueData *SpGistPageOpaque; #define SPGIST_LEAF (1<<2) #define SPGIST_NULLS (1<<3) -#define SpGistPageGetOpaque(page) ((SpGistPageOpaque) PageGetSpecialPointer(page)) +#define SpGistPageGetOpaque(page) \ + ((SpGistPageOpaque) PageGetSpecialOpaque(page, SpGistPageOpaqueData)) #define SpGistPageIsMeta(page) (SpGistPageGetOpaque(page)->flags & SPGIST_META) #define SpGistPageIsDeleted(page) (SpGistPageGetOpaque(page)->flags & SPGIST_DELETED) #define SpGistPageIsLeaf(page) (SpGistPageGetOpaque(page)->flags & SPGIST_LEAF) diff --git a/src/include/storage/bufpage.h b/src/include/storage/bufpage.h index e9f253f2c8..e96595f338 100644 --- a/src/include/storage/bufpage.h +++ b/src/include/storage/bufpage.h @@ -329,6 +329,20 @@ PageValidateSpecialPointer(Page page) (char *) ((char *) (page) + ((PageHeader) (page))->pd_special) \ ) +/* + * PageGetSpecialOpaque + * Returns pointer to special space on a page, of the given type. + * This removes the data dependency on the page header in builds + * without asserts enabled. + */ +#define PageGetSpecialOpaque(page, OpaqueDataType) \ +( \ + AssertMacro(PageGetPageSize(page) == BLCKSZ && \ + PageGetSpecialSize(page) == MAXALIGN(sizeof(OpaqueDataType))), \ + (OpaqueDataType *) ((char *) (page) + \ + (BLCKSZ - MAXALIGN(sizeof(OpaqueDataType)))) \ +) + /* * PageGetItem * Retrieves an item on the given page. -- 2.30.2 ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-05 19:45 Robert Haas <[email protected]> parent: Matthias van de Meent <[email protected]> 0 siblings, 2 replies; 128+ messages in thread From: Robert Haas @ 2022-04-05 19:45 UTC (permalink / raw) To: Matthias van de Meent <[email protected]>; +Cc: Michael Paquier <[email protected]>; pgsql-hackers On Fri, Apr 1, 2022 at 11:12 AM Matthias van de Meent <[email protected]> wrote: > Here's a new 0001 to keep CFBot happy. This seems like it would conflict with the proposal from http://postgr.es/m/CA+TgmoaD8wMN6i1mmuo+4ZNeGE3Hd57ys8uV8UZm7cneqy3W2g@mail.gmail.com which I still hope to advance in some form at an appropriate time. -- Robert Haas EDB: http://www.enterprisedb.com ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 08:33 Matthias van de Meent <[email protected]> parent: Robert Haas <[email protected]> 1 sibling, 1 reply; 128+ messages in thread From: Matthias van de Meent @ 2022-04-07 08:33 UTC (permalink / raw) To: Robert Haas <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers On Tue, 5 Apr 2022 at 21:45, Robert Haas <[email protected]> wrote: > > On Fri, Apr 1, 2022 at 11:12 AM Matthias van de Meent > <[email protected]> wrote: > > Here's a new 0001 to keep CFBot happy. > > This seems like it would conflict with the proposal from > http://postgr.es/m/CA+TgmoaD8wMN6i1mmuo+4ZNeGE3Hd57ys8uV8UZm7cneqy3W2g@mail.gmail.com > which I still hope to advance in some form at an appropriate time. I can see why what would be the case. However, I don't think that is of much importance here, as reverting the changes that are yet to be committed would be trivial. Also, I can't see why we would allow page-level layout changes in initdb; that seems like the wrong place to do that. All page layout currently is at compile-time; even checksums (which can be enabled/disabled in initdb) have reserved space available in the page header. Why would it be different for nonces? I don't think that the 'storing an explicit nonce' patch would conflict in any meaningful form, other than maybe needing to roll back from PageGetSpecialOpaque to PageGetSpecialPointer when (if) the nonce is indeed going to be stored in the special area of each page with a size defined during initdb. Until then, we could have a nice (but small) performance boost. -Matthias ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 08:49 Pavel Borisov <[email protected]> parent: Robert Haas <[email protected]> 1 sibling, 0 replies; 128+ messages in thread From: Pavel Borisov @ 2022-04-07 08:49 UTC (permalink / raw) To: Robert Haas <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers > > On Fri, Apr 1, 2022 at 11:12 AM Matthias van de Meent > <[email protected]> wrote: > > Here's a new 0001 to keep CFBot happy. > > This seems like it would conflict with the proposal from > > http://postgr.es/m/CA+TgmoaD8wMN6i1mmuo+4ZNeGE3Hd57ys8uV8UZm7cneqy3W2g@mail.gmail.com > which I still hope to advance in some form at an appropriate time. > It may be weakly related to the current discussion, but I'd like to note that the other proposed patch for making XID's 64-bit [1] will store per-page-common xid data in the heap page special area. It doesn't contradict storing a nonce in this area also, but I'd appreciate it if we could avoid changing heap page special layout twice. [1] https://www.postgresql.org/message-id/flat/CACG%3DezZe1NQSCnfHOr78AtAZxJZeCvxrts0ygrxYwe%3DpyyjVWA%4... ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 14:01 Robert Haas <[email protected]> parent: Matthias van de Meent <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Robert Haas @ 2022-04-07 14:01 UTC (permalink / raw) To: Matthias van de Meent <[email protected]>; +Cc: Michael Paquier <[email protected]>; pgsql-hackers On Thu, Apr 7, 2022 at 4:34 AM Matthias van de Meent <[email protected]> wrote: > Also, I can't see why we would allow page-level layout changes in > initdb; that seems like the wrong place to do that. All page layout > currently is at compile-time; even checksums (which can be > enabled/disabled in initdb) have reserved space available in the page > header. Why would it be different for nonces? Because there's no place to put them in the existing page format. We jammed checksums into the 2-byte field that had previously been set aside for the TLI, but that wasn't really an ideal solution because it meant we ended up with a checksum that is only 16 bits wide. However, the 2 bytes set aside for the TLI weren't really being used effectively anyway, so repurposing them was relatively easy, and a 16-bit checksum is better than nothing. For encryption or integrity verification, you need a lot more space, like 16-32 bytes. I can't see us adding that unilaterally to every cluster, because (1) it would break pg_upgrade compatibility, (2) it's a pretty significant amount of space to set aside in every single cluster whether it is using those features or not, and (3) the technology is constantly evolving and we can't predict how many bytes will be needed in the future. AES in whatever mode we use it requires whatever number of bytes it does, but AES replaced DES and will in turn be replaced by something else which can have totally different requirements. I do understand that there are significant challenges and performance concerns around having these kinds of initdb-controlled page layout changes, so the future of that patch is unclear. However, I don't think that it's practical to say that a 16-bit checksum should be good enough for everyone, and I also don't think it's practical to say that if you want a wider checksum or to use encryption or whatever, you have to recompile from source. Most users are going to get precompiled binaries from a vendor, and those binaries need to be able to work in all the configurations that users want to use. It's OK for experimental things that we only expect developers to fool with to require recompiling, but things that users have a legitimate need to reconfigure need to be initdb-time controllable at worst. Hence fc49e24fa69a15efacd5b8958115ed9c43c48f9a, for example. -- Robert Haas EDB: http://www.enterprisedb.com ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 18:42 Peter Geoghegan <[email protected]> parent: Robert Haas <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Peter Geoghegan @ 2022-04-07 18:42 UTC (permalink / raw) To: Robert Haas <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers On Thu, Apr 7, 2022 at 7:01 AM Robert Haas <[email protected]> wrote: > Because there's no place to put them in the existing page format. We > jammed checksums into the 2-byte field that had previously been set > aside for the TLI, but that wasn't really an ideal solution because it > meant we ended up with a checksum that is only 16 bits wide. However, > the 2 bytes set aside for the TLI weren't really being used > effectively anyway, so repurposing them was relatively easy, and a > 16-bit checksum is better than nothing. But if we were in a green-field situation we'd probably not want to use up several bytes for a nonse anyway. You said so yourself. > I do understand that there are significant challenges and performance > concerns around having these kinds of initdb-controlled page layout > changes, so the future of that patch is unclear. Why does it need to be at initdb time? Though I cannot prove it, I suspect that the original intent of the special area was to support an additional (though typically small) variable length array, that works a little like the current line pointer array. This array would have to grow backwards (newer items get appended at earlier physical offsets), unlike our line pointer array (which gets appended to at the end, in the simple and obvious way). Growing backwards like this happens with DB systems, that store their line pointer array at the end of the page(the traditional approach from the System R days, I believe). Supporting a variable-length special area array like this would mean that any time you add a new item to the variable-sized array in the special area, the page's entire tuple space has to be memmove()'d backwards by a couple of bytes to create the required space. And so the relevant bufpage.c routine would have to adjust the whole line pointer array such that each lp_off received a compensating adjustment. The array might only be for some kind of page-level transaction metadata, something like that -- shifting it around is pretty expensive (reusing existing slots isn't too expensive, though). Why can't it work like that? You don't really need to build the full set of bufpage.c facilities (though it might not be a bad idea to fully support these variable-length arrays, which seem like they might come in handy). That seems perfectly compatible with what Matthias wants to do, provided we're willing to deem the special area struct (e.g. BTOpaque) as always coming "first" (which is essentially the same as his current proposal anyway). You can even do the same thing yourself for the nonse (use a fixed, known offset), with relatively modest effort. You'd need to have AM-specific knowledge (it would stack right on top of Matthias's technique), but that doesn't seem all that hard. There are plenty of remaining status bits in BTOpaque, and probably all other index AM special areas. -- Peter Geoghegan ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 19:11 Robert Haas <[email protected]> parent: Peter Geoghegan <[email protected]> 0 siblings, 3 replies; 128+ messages in thread From: Robert Haas @ 2022-04-07 19:11 UTC (permalink / raw) To: Peter Geoghegan <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers On Thu, Apr 7, 2022 at 2:43 PM Peter Geoghegan <[email protected]> wrote: > But if we were in a green-field situation we'd probably not want to > use up several bytes for a nonse anyway. You said so yourself. I don't know what statement of mine you're talking about here, and while I don't love using up space for a nonce, it seems to be the way this encryption stuff works. I don't see that there's a reasonable alternative, green field or no. > > I do understand that there are significant challenges and performance > > concerns around having these kinds of initdb-controlled page layout > > changes, so the future of that patch is unclear. > > Why does it need to be at initdb time? > > Though I cannot prove it, I suspect that the original intent of the > special area was to support an additional (though typically small) > variable length array, that works a little like the current line > pointer array. This array would have to grow backwards (newer items > get appended at earlier physical offsets), unlike our line pointer > array (which gets appended to at the end, in the simple and obvious > way). Growing backwards like this happens with DB systems, that store > their line pointer array at the end of the page(the traditional > approach from the System R days, I believe). > > Supporting a variable-length special area array like this would mean > that any time you add a new item to the variable-sized array in the > special area, the page's entire tuple space has to be memmove()'d > backwards by a couple of bytes to create the required space. And so > the relevant bufpage.c routine would have to adjust the whole line > pointer array such that each lp_off received a compensating > adjustment. The array might only be for some kind of page-level > transaction metadata, something like that -- shifting it around is > pretty expensive (reusing existing slots isn't too expensive, though). > > Why can't it work like that? You don't really need to build the full > set of bufpage.c facilities (though it might not be a bad idea to > fully support these variable-length arrays, which seem like they might > come in handy). That seems perfectly compatible with what Matthias > wants to do, provided we're willing to deem the special area struct > (e.g. BTOpaque) as always coming "first" (which is essentially the > same as his current proposal anyway). You can even do the same thing > yourself for the nonse (use a fixed, known offset), with relatively > modest effort. You'd need to have AM-specific knowledge (it would > stack right on top of Matthias's technique), but that doesn't seem all > that hard. There are plenty of remaining status bits in BTOpaque, and > probably all other index AM special areas. I'm not really following any of this. You seem to be arguing about whether it's possible to change the length of the special space *later* than initdb time. I agree that might have some use for some purpose, but for encryption it's not necessarily all that helpful because you have to be able to find the nonce on the page before you've decrypted it. If you don't know whether there's a nonce or where it's located, you can't do that. What Matthias and I were discussing is whether you have to make a decision about appending stuff to the special space *earlier* than initdb-time i.e. at compile time. My position is that if we need some space in every page to put a nonce, the best place to put it is at the very end of the page, within the special space and after anything else that is stored in the special space. Code that only manipulates the line pointer array and tuple data won't care, because pd_special will just be a bit smaller than it would otherwise have been, and none of that code looks at any byte offset >= pd_special. Code that looks at the special space won't care either, as long as it uses PageGetSpecialPointer to find the data, and doesn't examine how large the special space actually is. That corresponds pretty well to how existing users of the special space work, so it seems pretty good. If we *didn't* put the nonce at the end of the page, where else would we put it? It has to be at a fixed offset, because otherwise you can't find it without decrypting the page first, which would be circular. You could put it at the beginning of the page, or after the page header and before the line pointer array, but either of those things seem likely to affect a lot more code, because there's a lot more stuff that accesses the line pointer array than the special space. -- Robert Haas EDB: http://www.enterprisedb.com ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 19:27 Peter Geoghegan <[email protected]> parent: Robert Haas <[email protected]> 2 siblings, 1 reply; 128+ messages in thread From: Peter Geoghegan @ 2022-04-07 19:27 UTC (permalink / raw) To: Robert Haas <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers On Thu, Apr 7, 2022 at 12:11 PM Robert Haas <[email protected]> wrote: > I don't know what statement of mine you're talking about here, and > while I don't love using up space for a nonce, it seems to be the way > this encryption stuff works. I don't see that there's a reasonable > alternative, green field or no. I just meant that it wouldn't be reasonable to impose a fixed cost on every user, even those not using the feature. Which you said yourself. > I'm not really following any of this. You seem to be arguing about > whether it's possible to change the length of the special space > *later* than initdb time. I agree that might have some use for some > purpose, but for encryption it's not necessarily all that helpful > because you have to be able to find the nonce on the page before > you've decrypted it. If you don't know whether there's a nonce or > where it's located, you can't do that. What if you just encrypt a significant subset of the page, and leave a small amount of metadata that can be read without decryption? Is that approach feasible? I think that you could even encrypt the line pointer array (not just the tuple space), without breaking anything. > What Matthias and I were > discussing is whether you have to make a decision about appending > stuff to the special space *earlier* than initdb-time i.e. at compile > time. I got that much, of course. That will work, I suppose, but it'll be the first and last time that anybody gets to do that (unless we accept it being incompatible with encryption). > That corresponds pretty well to how existing users of the special > space work, so it seems pretty good. I think that it still needs to be accounted for in a bunch of places. In particular anywhere concerned with page-level space management. For example the definition of "1/3 of a page" used to enforce the limit on the maximum size of an nbtree index tuple will need to account for the presence of a nonse, either way. > If we *didn't* put the nonce at the end of the page, where else would > we put it? It has to be at a fixed offset, because otherwise you can't > find it without decrypting the page first, which would be circular. Immediately before the special area proper (say BTOpaque), which would "logically come after" the special space under this scheme. You wouldn't have a simple constant offset into the page, but you'd have something not too far removed from such a constant. It could work as a constant with minimal context (just the AM type). Just like with Matthias' patch. -- Peter Geoghegan ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 19:37 Robert Haas <[email protected]> parent: Peter Geoghegan <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Robert Haas @ 2022-04-07 19:37 UTC (permalink / raw) To: Peter Geoghegan <[email protected]>; +Cc: Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers On Thu, Apr 7, 2022 at 3:27 PM Peter Geoghegan <[email protected]> wrote: > I just meant that it wouldn't be reasonable to impose a fixed cost on > every user, even those not using the feature. Which you said yourself. Unfortunately, I think there's bound to be some cost. We can avoid using the space in the page for every user, but anything that makes the page layout variable is going to cost some number of CPU cycles someplace. We have to measure that overhead and see if it's small enough that we're OK with it. > I got that much, of course. That will work, I suppose, but it'll be > the first and last time that anybody gets to do that (unless we accept > it being incompatible with encryption). Yeah. > > If we *didn't* put the nonce at the end of the page, where else would > > we put it? It has to be at a fixed offset, because otherwise you can't > > find it without decrypting the page first, which would be circular. > > Immediately before the special area proper (say BTOpaque), which would > "logically come after" the special space under this scheme. You > wouldn't have a simple constant offset into the page, but you'd have > something not too far removed from such a constant. It could work as a > constant with minimal context (just the AM type). Just like with > Matthias' patch. I don't think this would work, because I don't think it would be practical to always know the AM type. Think about applying an XLOG_FPI record, for example. -- Robert Haas EDB: http://www.enterprisedb.com ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 20:09 Stephen Frost <[email protected]> parent: Robert Haas <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Stephen Frost @ 2022-04-07 20:09 UTC (permalink / raw) To: Robert Haas <[email protected]>; +Cc: Peter Geoghegan <[email protected]>; Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers Greetings, * Robert Haas ([email protected]) wrote: > On Thu, Apr 7, 2022 at 3:27 PM Peter Geoghegan <[email protected]> wrote: > > I just meant that it wouldn't be reasonable to impose a fixed cost on > > every user, even those not using the feature. Which you said yourself. > > Unfortunately, I think there's bound to be some cost. We can avoid > using the space in the page for every user, but anything that makes > the page layout variable is going to cost some number of CPU cycles > someplace. We have to measure that overhead and see if it's small > enough that we're OK with it. Agreed that there may be some cost in CPU cycles for folks who don't initialize the database with an option that needs this, but hopefully that'll be quite small. > > I got that much, of course. That will work, I suppose, but it'll be > > the first and last time that anybody gets to do that (unless we accept > > it being incompatible with encryption). > > Yeah. I don't know that I agree with this being the 'first and last time'..? If we have two options that could work together and each need some amount of per-page space, such as a nonce or authentication tag, we'd just need to be able to track which of those are enabled (eg: through pg_control) and then know which gets what space. I don't see why we couldn't add something today and then add something else later on. I do think there'll likely be cases where we have two options that don't make sense together and we wouldn't wish to allow that (such as page-level strong checksums and authenticated encryption, as the latter provides the former inherently) but there could certainly be things that do work together too. > > > If we *didn't* put the nonce at the end of the page, where else would > > > we put it? It has to be at a fixed offset, because otherwise you can't > > > find it without decrypting the page first, which would be circular. > > > > Immediately before the special area proper (say BTOpaque), which would > > "logically come after" the special space under this scheme. You > > wouldn't have a simple constant offset into the page, but you'd have > > something not too far removed from such a constant. It could work as a > > constant with minimal context (just the AM type). Just like with > > Matthias' patch. > > I don't think this would work, because I don't think it would be > practical to always know the AM type. Think about applying an XLOG_FPI > record, for example. I'm also doubtful about how well this would work, but the other question is- what would be the advantage to doing it this way? If we could have it be run-time instead of initdb-time, that'd be great (imagine a database that's encrypted while another isn't in the same cluster, or even individual tables, which would all be very cool), but I don't think this approach would make that possible..? (sorry for only just seeing this thread getting traction, have been a bit busy with other things ...) Thanks, Stephen Attachments: [application/pgp-signature] signature.asc (819B, ../../[email protected]/2-signature.asc) download ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-07 21:53 Matthias van de Meent <[email protected]> parent: Robert Haas <[email protected]> 2 siblings, 0 replies; 128+ messages in thread From: Matthias van de Meent @ 2022-04-07 21:53 UTC (permalink / raw) To: Robert Haas <[email protected]>; +Cc: Peter Geoghegan <[email protected]>; Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers On Thu, 7 Apr 2022 at 21:11, Robert Haas <[email protected]> wrote: > > On Thu, Apr 7, 2022 at 2:43 PM Peter Geoghegan <[email protected]> wrote: > > But if we were in a green-field situation we'd probably not want to > > use up several bytes for a nonse anyway. You said so yourself. > > I don't know what statement of mine you're talking about here, and > while I don't love using up space for a nonce, it seems to be the way > this encryption stuff works. I don't see that there's a reasonable > alternative, green field or no. > > > > I do understand that there are significant challenges and performance > > > concerns around having these kinds of initdb-controlled page layout > > > changes, so the future of that patch is unclear. > > > > Why does it need to be at initdb time? > > > > Though I cannot prove it, I suspect that the original intent of the > > special area was to support an additional (though typically small) > > variable length array, that works a little like the current line > > pointer array. This array would have to grow backwards (newer items > > get appended at earlier physical offsets), unlike our line pointer > > array (which gets appended to at the end, in the simple and obvious > > way). Growing backwards like this happens with DB systems, that store > > their line pointer array at the end of the page(the traditional > > approach from the System R days, I believe). > > > > Supporting a variable-length special area array like this would mean > > that any time you add a new item to the variable-sized array in the > > special area, the page's entire tuple space has to be memmove()'d > > backwards by a couple of bytes to create the required space. And so > > the relevant bufpage.c routine would have to adjust the whole line > > pointer array such that each lp_off received a compensating > > adjustment. The array might only be for some kind of page-level > > transaction metadata, something like that -- shifting it around is > > pretty expensive (reusing existing slots isn't too expensive, though). > > > > Why can't it work like that? You don't really need to build the full > > set of bufpage.c facilities (though it might not be a bad idea to > > fully support these variable-length arrays, which seem like they might > > come in handy). That seems perfectly compatible with what Matthias > > wants to do, provided we're willing to deem the special area struct > > (e.g. BTOpaque) as always coming "first" (which is essentially the > > same as his current proposal anyway). You can even do the same thing > > yourself for the nonse (use a fixed, known offset), with relatively > > modest effort. You'd need to have AM-specific knowledge (it would > > stack right on top of Matthias's technique), but that doesn't seem all > > that hard. There are plenty of remaining status bits in BTOpaque, and > > probably all other index AM special areas. > > I'm not really following any of this. You seem to be arguing about > whether it's possible to change the length of the special space > *later* than initdb time. I agree that might have some use for some > purpose, but for encryption it's not necessarily all that helpful > because you have to be able to find the nonce on the page before > you've decrypted it. If you don't know whether there's a nonce or > where it's located, you can't do that. What Matthias and I were > discussing is whether you have to make a decision about appending > stuff to the special space *earlier* than initdb-time i.e. at compile > time. > > My position is that if we need some space in every page to put a > nonce, the best place to put it is at the very end of the page, within > the special space and after anything else that is stored in the > special space. Code that only manipulates the line pointer array and > tuple data won't care, because pd_special will just be a bit smaller > than it would otherwise have been, and none of that code looks at any > byte offset >= pd_special. Code that looks at the special space won't > care either, as long as it uses PageGetSpecialPointer to find the > data, and doesn't examine how large the special space actually is. > That corresponds pretty well to how existing users of the special > space work, so it seems pretty good. Except that reserving space on each page requires recalculation of all variables that depend on the amount of potential free space available on a page (for some cases this is less important, for some it is critical that the value is not wrong). If this is always done at runtime then that can cause significant overhead. > If we *didn't* put the nonce at the end of the page, where else would > we put it? It has to be at a fixed offset, because otherwise you can't > find it without decrypting the page first, which would be circular. I think there's no specifically good reason why we'd need to put the nonce in storage at the same place as where we reserve the space for the nonce in the unencrypted in-memory format. > You could put it at the beginning of the page, or after the page > header and before the line pointer array, but either of those things > seem likely to affect a lot more code, because there's a lot more > stuff that accesses the line pointer array than the special space. I'm not too keen on anything related to having no page layout guarantees. I can understand needing a nonce; but couldn't that be put somewhere different than smack-dab in the middle of what are considered AM-controlled areas? I'm not certain why we need lsn on a page after we've checked that we flushed all WAL up to that LSN. That is, right now we store the LSN in the in-memory representation of the page because we need it to check that the WAL is flushed up to that point when we write out the page, so that we can recover the data in case of disk write issues. But after flushing the WAL to disk, this LSN on the page is not needed anymore, and could thus be replaced with a nonce. When reading such page, the LSN-now-nonce can be replaced with the latest flushed LSN to prevent unwanted xlog flushes. Sure, this limits nonce to 8 bytes, but if you really need more than that IMO you can recompile from scratch with a bigger PageHeader. Benefit of using existing pageheader structs is that we could enable TDE on a relation level and on existing clusters - there's no extra space needed right now as there's already some space available. Yes, we'd lose the ability to skip redo on pages, but I think that's a small price to pay when you enable TDE. -Matthias ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-04-18 20:04 Bruce Momjian <[email protected]> parent: Robert Haas <[email protected]> 2 siblings, 1 reply; 128+ messages in thread From: Bruce Momjian @ 2022-04-18 20:04 UTC (permalink / raw) To: Robert Haas <[email protected]>; +Cc: Peter Geoghegan <[email protected]>; Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers On Thu, Apr 7, 2022 at 03:11:24PM -0400, Robert Haas wrote: > On Thu, Apr 7, 2022 at 2:43 PM Peter Geoghegan <[email protected]> wrote: > > But if we were in a green-field situation we'd probably not want to > > use up several bytes for a nonse anyway. You said so yourself. > > I don't know what statement of mine you're talking about here, and > while I don't love using up space for a nonce, it seems to be the way > this encryption stuff works. I don't see that there's a reasonable > alternative, green field or no. Uh, XTS doesn't require a nonce, so why are talking about nonces in this thread? -- Bruce Momjian <[email protected]> https://momjian.us EDB https://enterprisedb.com Indecision is a decision. Inaction is an action. Mark Batterson ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-11-28 22:31 Tom Lane <[email protected]> parent: Bruce Momjian <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Tom Lane @ 2022-11-28 22:31 UTC (permalink / raw) To: Bruce Momjian <[email protected]>; +Cc: Robert Haas <[email protected]>; Peter Geoghegan <[email protected]>; Matthias van de Meent <[email protected]>; Michael Paquier <[email protected]>; pgsql-hackers Bruce Momjian <[email protected]> writes: > Uh, XTS doesn't require a nonce, so why are talking about nonces in this > thread? Because some other proposals do, or could, require a per-page nonce. After looking through this thread, I side with Robert: we should reject the remainder of this patch. It gives up page layout flexibility that we might want back someday. Moreover, I didn't see any hard evidence offered that there's any actual performance gain, let alone such a compelling gain that we should give up that flexibility for it. regards, tom lane ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-11-29 00:22 Michael Paquier <[email protected]> parent: Tom Lane <[email protected]> 0 siblings, 1 reply; 128+ messages in thread From: Michael Paquier @ 2022-11-29 00:22 UTC (permalink / raw) To: Tom Lane <[email protected]>; +Cc: Bruce Momjian <[email protected]>; Robert Haas <[email protected]>; Peter Geoghegan <[email protected]>; Matthias van de Meent <[email protected]>; pgsql-hackers On Mon, Nov 28, 2022 at 05:31:50PM -0500, Tom Lane wrote: > After looking through this thread, I side with Robert: we should reject > the remainder of this patch. It gives up page layout flexibility that > we might want back someday. Moreover, I didn't see any hard evidence > offered that there's any actual performance gain, let alone such a > compelling gain that we should give up that flexibility for it. As far as I understand, we are talking about this one: https://www.postgresql.org/message-id/[email protected]... After a few months looking at it again, I cannot get much excited about switching these routines from a logic where we look at the page header to something where we'd rely on the opaque structure size. I am wondering if it would be worth adding an AssertMacro() like in this one, though: https://www.postgresql.org/message-id/[email protected] This still uses PageGetSpecialPointer() to retrieve the pointer area from the page header, but it also checks that we have a match with the structure expected by the index AM. -- Michael Attachments: [application/pgp-signature] signature.asc (833B, ../../[email protected]/2-signature.asc) download ^ permalink raw reply [nested|flat] 128+ messages in thread
* Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas @ 2022-11-29 00:48 Tom Lane <[email protected]> parent: Michael Paquier <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tom Lane @ 2022-11-29 00:48 UTC (permalink / raw) To: Michael Paquier <[email protected]>; +Cc: Bruce Momjian <[email protected]>; Robert Haas <[email protected]>; Peter Geoghegan <[email protected]>; Matthias van de Meent <[email protected]>; pgsql-hackers Michael Paquier <[email protected]> writes: > I am wondering if it would be worth adding an AssertMacro() like in > this one, though: > https://www.postgresql.org/message-id/[email protected] Kind of doubt it. It'd bloat debug builds with a lot of redundant checks, and probably never catch anything. For catching problems in production, the right place to do this (and where we already do do it) is in _bt_checkpage. If any of the other AMs lack page-read-time sanity checks like _bt_checkpage, I'd be in favor of adding that. But I don't think a whole bunch of additional checks afterwards will buy much. regards, tom lane ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v1 4/7] Row pattern recognition patch (executor). @ 2023-06-25 11:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 223 +++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 274 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 12 ++ src/include/windowapi.h | 9 + 5 files changed, 517 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..ae997dff86 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2762,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2849,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2900,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3242,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3582,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3784,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3821,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..63b225271c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -39,7 +42,9 @@ typedef struct static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +718,270 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + PG_RETURN_DATUM(result); + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..bc95c5fe9b 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,13 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('*', '+' or '?'. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2562,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Sun_Jun_25_21_05_09_2023_126)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v1-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v1 4/7] Row pattern recognition patch (executor). @ 2023-06-25 11:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 223 +++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 274 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 12 ++ src/include/windowapi.h | 9 + 5 files changed, 517 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..ae997dff86 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2762,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2849,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2900,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3242,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3582,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3784,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3821,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..63b225271c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -39,7 +42,9 @@ typedef struct static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +718,270 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + PG_RETURN_DATUM(result); + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..bc95c5fe9b 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,13 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('*', '+' or '?'. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2562,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Sun_Jun_25_21_05_09_2023_126)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v1-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v1 4/7] Row pattern recognition patch (executor). @ 2023-06-25 11:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 223 +++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 274 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 12 ++ src/include/windowapi.h | 9 + 5 files changed, 517 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..ae997dff86 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2762,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2849,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2900,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3242,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3582,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3784,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3821,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..63b225271c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -39,7 +42,9 @@ typedef struct static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +718,270 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + PG_RETURN_DATUM(result); + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..bc95c5fe9b 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,13 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('*', '+' or '?'. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2562,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Sun_Jun_25_21_05_09_2023_126)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v1-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v1 4/7] Row pattern recognition patch (executor). @ 2023-06-25 11:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 223 +++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 274 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 12 ++ src/include/windowapi.h | 9 + 5 files changed, 517 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..ae997dff86 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2762,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2849,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2900,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3242,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3582,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3784,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3821,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..63b225271c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -39,7 +42,9 @@ typedef struct static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +718,270 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + PG_RETURN_DATUM(result); + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..bc95c5fe9b 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,13 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('*', '+' or '?'. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2562,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Sun_Jun_25_21_05_09_2023_126)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v1-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v1 4/7] Row pattern recognition patch (executor). @ 2023-06-25 11:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 223 +++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 274 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 12 ++ src/include/windowapi.h | 9 + 5 files changed, 517 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..ae997dff86 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2762,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2849,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2900,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3242,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3582,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3784,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3821,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..63b225271c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -39,7 +42,9 @@ typedef struct static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +718,270 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + PG_RETURN_DATUM(result); + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..bc95c5fe9b 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,13 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('*', '+' or '?'. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2562,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Sun_Jun_25_21_05_09_2023_126)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v1-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v2 4/7] Row pattern recognition patch (executor). @ 2023-06-26 08:05 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 225 +++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 302 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 13 ++ src/include/windowapi.h | 9 + 5 files changed, 548 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..bef2bc62b2 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,71 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2764,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2851,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2902,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3244,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3584,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3786,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3823,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..74ef11ce55 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,10 +39,21 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +727,289 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + SkipContext *context = NULL; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context = (SkipContext *) WinGetPartitionLocalMemory(winobj, sizeof(SkipContext)); + if (curr_pos < context->pos) + { + elog(DEBUG1, "skip this row: curr_pos: " INT64_FORMAT "context->pos: " INT64_FORMAT, + curr_pos, context->pos); + PG_RETURN_NULL(); + } + } + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + { + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context->pos += relpos; + elog(DEBUG1, "context->pos: " INT64_FORMAT, context->pos); + } + PG_RETURN_DATUM(result); + } + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..1643eaa6f1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Mon_Jun_26_17_45_07_2023_724)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v2-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v2 4/7] Row pattern recognition patch (executor). @ 2023-06-26 08:05 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 225 +++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 302 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 13 ++ src/include/windowapi.h | 9 + 5 files changed, 548 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..bef2bc62b2 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,71 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2764,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2851,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2902,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3244,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3584,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3786,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3823,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..74ef11ce55 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,10 +39,21 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +727,289 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + SkipContext *context = NULL; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context = (SkipContext *) WinGetPartitionLocalMemory(winobj, sizeof(SkipContext)); + if (curr_pos < context->pos) + { + elog(DEBUG1, "skip this row: curr_pos: " INT64_FORMAT "context->pos: " INT64_FORMAT, + curr_pos, context->pos); + PG_RETURN_NULL(); + } + } + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + { + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context->pos += relpos; + elog(DEBUG1, "context->pos: " INT64_FORMAT, context->pos); + } + PG_RETURN_DATUM(result); + } + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..1643eaa6f1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Mon_Jun_26_17_45_07_2023_724)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v2-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v2 4/7] Row pattern recognition patch (executor). @ 2023-06-26 08:05 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 225 +++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 302 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 13 ++ src/include/windowapi.h | 9 + 5 files changed, 548 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..bef2bc62b2 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,71 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2764,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2851,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2902,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3244,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3584,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3786,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3823,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..74ef11ce55 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,10 +39,21 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +727,289 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + SkipContext *context = NULL; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context = (SkipContext *) WinGetPartitionLocalMemory(winobj, sizeof(SkipContext)); + if (curr_pos < context->pos) + { + elog(DEBUG1, "skip this row: curr_pos: " INT64_FORMAT "context->pos: " INT64_FORMAT, + curr_pos, context->pos); + PG_RETURN_NULL(); + } + } + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + { + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context->pos += relpos; + elog(DEBUG1, "context->pos: " INT64_FORMAT, context->pos); + } + PG_RETURN_DATUM(result); + } + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..1643eaa6f1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Mon_Jun_26_17_45_07_2023_724)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v2-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v2 4/7] Row pattern recognition patch (executor). @ 2023-06-26 08:05 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 225 +++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 302 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 13 ++ src/include/windowapi.h | 9 + 5 files changed, 548 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..bef2bc62b2 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,71 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2764,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2851,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2902,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3244,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3584,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3786,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3823,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..74ef11ce55 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,10 +39,21 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +727,289 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + SkipContext *context = NULL; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context = (SkipContext *) WinGetPartitionLocalMemory(winobj, sizeof(SkipContext)); + if (curr_pos < context->pos) + { + elog(DEBUG1, "skip this row: curr_pos: " INT64_FORMAT "context->pos: " INT64_FORMAT, + curr_pos, context->pos); + PG_RETURN_NULL(); + } + } + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + { + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context->pos += relpos; + elog(DEBUG1, "context->pos: " INT64_FORMAT, context->pos); + } + PG_RETURN_DATUM(result); + } + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..1643eaa6f1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Mon_Jun_26_17_45_07_2023_724)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v2-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v2 4/7] Row pattern recognition patch (executor). @ 2023-06-26 08:05 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 225 +++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 302 ++++++++++++++++++++++++++- src/include/catalog/pg_proc.dat | 9 + src/include/nodes/execnodes.h | 13 ++ src/include/windowapi.h | 9 + 5 files changed, 548 insertions(+), 10 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..bef2bc62b2 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -48,6 +48,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +160,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -195,9 +204,9 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -2388,6 +2397,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2498,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2692,71 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + if (func->winfnoid != F_RPR) + continue; + + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "RPR must have 1 argument but function %d has %d args", func->winfnoid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "RPR's arg is not Var"); + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2764,76 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2851,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2902,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3244,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3420,14 +3584,53 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3583,15 +3786,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3823,9 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..74ef11ce55 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,10 +39,21 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - +static bool get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos); +static int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result); /* * utility routine for *_rank functions. @@ -713,3 +727,289 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * rpr + * allow to use "Row pattern recognition: WINDOW clause" (SQL:2016 R020) in + * the target list. + * Usage: SELECT rpr(colname) OVER (..) + * where colname is defined in PATTERN clause. + */ +Datum +window_rpr(PG_FUNCTION_ARGS) +{ +#define MAX_PATTERNS 16 /* max variables in PATTERN clause */ + + WindowObject winobj = PG_WINDOW_OBJECT(); + WindowAggState *winstate = WinGetAggState(winobj); + Datum result; + bool expression_result; + bool isnull; + int relpos; + int64 curr_pos, markpos; + ListCell *lc, *lc1; + SkipContext *context = NULL; + + curr_pos = WinGetCurrentPosition(winobj); + elog(DEBUG1, "rpr is called. row: " INT64_FORMAT, curr_pos); + + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context = (SkipContext *) WinGetPartitionLocalMemory(winobj, sizeof(SkipContext)); + if (curr_pos < context->pos) + { + elog(DEBUG1, "skip this row: curr_pos: " INT64_FORMAT "context->pos: " INT64_FORMAT, + curr_pos, context->pos); + PG_RETURN_NULL(); + } + } + + /* + * Evaluate PATTERN until one of expressions is not true or out of frame. + */ + relpos = 0; + + forboth(lc, winstate->patternVariableList, lc1, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc)); + char *quantifier = strVal(lfirst(lc1)); + + elog(DEBUG1, "relpos: %d pattern vname: %s quantifier: %s", relpos, vname, quantifier); + + /* evaluate row pattern against current row */ + relpos = evaluate_pattern(winobj, winstate, relpos, vname, quantifier, &expression_result); + + /* + * If the expression did not match, we are done. + */ + if (!expression_result) + break; + + /* out of frame? */ + if (relpos < 0) + break; + + /* count up relative row position */ + relpos++; + } + + elog(DEBUG1, "relpos: %d", relpos); + + /* + * If current row satified the pattern, return argument expression. + */ + if (expression_result) + { + result = WinGetFuncArgInFrame(winobj, 0, + 0, WINDOW_SEEK_HEAD, false, + &isnull, NULL); + } + + /* + * At this point we can set mark down to current pos -2. + */ + markpos = curr_pos -2; + elog(DEBUG1, "markpos: " INT64_FORMAT, markpos); + if (markpos >= 0) + WinSetMarkPosition(winobj, markpos); + + if (expression_result) + { + if (winstate->rpSkipTo == ST_PAST_LAST_ROW) + { + context->pos += relpos; + elog(DEBUG1, "context->pos: " INT64_FORMAT, context->pos); + } + PG_RETURN_DATUM(result); + } + + PG_RETURN_NULL(); +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match relative row position + * -1: current row is out of frame + */ +static +int evaluate_pattern(WindowObject winobj, WindowAggState *winstate, + int relpos, char *vname, char *quantifier, bool *result) +{ + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + int sts; + bool out_of_frame = false; + bool isnull; + StringInfo encoded_str = makeStringInfo(); + char pattern_str[128]; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + bool second_try_match = false; + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + for (;;) + { + if (!get_slots(winobj, winstate, relpos)) + { + out_of_frame = true; + break; /* current row is out of frame */ + } + + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: %d", vname, relpos); + break; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: %d", vname, relpos); + break; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: %d", vname, relpos); + appendStringInfoChar(encoded_str, vname[0]); + + /* If quantifier is "+", we need to look for more matching row */ + if (quantifier && !strcmp(quantifier, "+")) + { + /* remember that we want to try another row */ + second_try_match = true; + relpos++; + } + else + break; + } + } + } + if (second_try_match) + relpos--; + + if (out_of_frame) + { + *result = false; + return -1; + } + + /* build regular expression */ + snprintf(pattern_str, sizeof(pattern_str), "%c%s", vname[0], quantifier); + + /* + * Do regular expression matching against sequence of rows satisfying + * the expression using regexp_instr(). + */ + sts = DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str->data)), + PointerGetDatum(cstring_to_text(pattern_str)))); + elog(DEBUG1, "regexp_instr returned: %d. str: %s regexp: %s", + sts, encoded_str->data, pattern_str); + *result = (sts > 0)? true : false; + } + return relpos; +} + +/* + * Get current, previous and next tuple. + * Returns true if still within frame. + */ +static bool +get_slots(WindowObject winobj, WindowAggState *winstate, int current_pos) +{ + TupleTableSlot *slot; + bool isnull, isout; + int sts; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* for current row */ + slot = winstate->temp_slot_1; + sts = WinGetSlotInFrame(winobj, slot, + current_pos, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "current row is out of frame"); + econtext->ecxt_scantuple = winstate->null_slot; + return false; + } + else + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos - 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "previous row out of frame at: %d", current_pos); + econtext->ecxt_outertuple = winstate->null_slot; + } + econtext->ecxt_outertuple = slot; + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + sts = WinGetSlotInFrame(winobj, slot, + current_pos + 1, WINDOW_SEEK_HEAD, false, + &isnull, &isout); + if (sts < 0) + { + elog(DEBUG1, "next row out of frame at: %d", current_pos); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + + return true; +} + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..e3a9e0ffeb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,15 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'row pattern recognition in window', + proname => 'rpr', prokind => 'w', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_rpr' }, +{ oid => '6123', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6124', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..1643eaa6f1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,11 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..a0facf38fe 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,16 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Mon_Jun_26_17_45_07_2023_724)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v2-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v3 4/7] Row pattern recognition patch (executor). @ 2023-07-26 10:49 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-07-26 10:49 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 701 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 18 + src/include/windowapi.h | 8 + 5 files changed, 758 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..0586bf57d6 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +192,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +206,19 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); /* * initialize_windowaggregate @@ -673,6 +694,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +814,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +886,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +946,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +961,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +981,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1050,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2129,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2466,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2567,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2761,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + + /* sanity check */ + nargs = list_length(func->args); + if (nargs != 1) + continue; + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + continue; + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2831,77 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + elog(DEBUG1, "walker: varattno: %d varattnosyn: %d",attno, attnosyn); + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2919,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2970,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3312,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3332,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3652,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3766,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3843,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3867,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3904,400 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + appendStringInfoChar(pattern_str, vname[0]); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s quantifier: %s", vname, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, vname[0]); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + econtext->ecxt_outertuple = slot; + } + } + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..4fd3bd1a93 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Jul_26_21_21_34_2023_317)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v3-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v3 4/7] Row pattern recognition patch (executor). @ 2023-07-26 10:49 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-07-26 10:49 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 701 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 18 + src/include/windowapi.h | 8 + 5 files changed, 758 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..0586bf57d6 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +192,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +206,19 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); /* * initialize_windowaggregate @@ -673,6 +694,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +814,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +886,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +946,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +961,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +981,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1050,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2129,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2466,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2567,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2761,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + + /* sanity check */ + nargs = list_length(func->args); + if (nargs != 1) + continue; + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + continue; + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2831,77 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + elog(DEBUG1, "walker: varattno: %d varattnosyn: %d",attno, attnosyn); + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2919,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2970,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3312,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3332,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3652,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3766,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3843,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3867,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3904,400 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + appendStringInfoChar(pattern_str, vname[0]); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s quantifier: %s", vname, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, vname[0]); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + econtext->ecxt_outertuple = slot; + } + } + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..4fd3bd1a93 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Jul_26_21_21_34_2023_317)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v3-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v3 4/7] Row pattern recognition patch (executor). @ 2023-07-26 10:49 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-07-26 10:49 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 701 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 18 + src/include/windowapi.h | 8 + 5 files changed, 758 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..0586bf57d6 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +192,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +206,19 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); /* * initialize_windowaggregate @@ -673,6 +694,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +814,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +886,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +946,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +961,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +981,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1050,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2129,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2466,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2567,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2761,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + + /* sanity check */ + nargs = list_length(func->args); + if (nargs != 1) + continue; + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + continue; + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2831,77 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + elog(DEBUG1, "walker: varattno: %d varattnosyn: %d",attno, attnosyn); + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2919,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2970,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3312,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3332,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3652,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3766,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3843,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3867,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3904,400 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + appendStringInfoChar(pattern_str, vname[0]); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s quantifier: %s", vname, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, vname[0]); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + econtext->ecxt_outertuple = slot; + } + } + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..4fd3bd1a93 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Jul_26_21_21_34_2023_317)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v3-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v3 4/7] Row pattern recognition patch (executor). @ 2023-07-26 10:49 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-07-26 10:49 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 701 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 18 + src/include/windowapi.h | 8 + 5 files changed, 758 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..0586bf57d6 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,14 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Map between Var attno in a target list and the parsed attno. + */ +typedef struct AttnoMap { + List *attno; /* att number in target list (list of AttNumber) */ + List *attnosyn; /* parsed att number (list of AttNumber) */ +} AttnoMap; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +192,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +206,19 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node, AttnoMap *map); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); /* * initialize_windowaggregate @@ -673,6 +694,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +814,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +886,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +946,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +961,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +981,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1050,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2129,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2466,12 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + Var *var; + int nargs; + AttnoMap attnomap; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2567,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2761,69 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + + /* + * Collect mapping between varattno and varattnosyn in the targetlist. + * XXX: For now we only check RPR's argument. Eventually we have to + * recurse the targetlist to find out all mappings in Var nodes. + */ + attnomap.attno = NIL; + attnomap.attnosyn = NIL; + + foreach (l, node->plan.targetlist) + { + te = lfirst(l); + if (IsA(te->expr, WindowFunc)) + { + WindowFunc *func = (WindowFunc *)te->expr; + + /* sanity check */ + nargs = list_length(func->args); + if (nargs != 1) + continue; + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + continue; + + var = (Var *)expr; + elog(DEBUG1, "resname: %s varattno: %d varattnosyn: %d", + te->resname, var->varattno, var->varattnosyn); + attnomap.attno = lappend_int(attnomap.attno, var->varattno); + attnomap.attnosyn = lappend_int(attnomap.attnosyn, var->varattnosyn); + } + } + + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + /* tweak expr so that it referes to outer slot */ + attno_map((Node *)expr, &attnomap); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2831,77 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite Var node's varattno to the varattno which is used in the target + * list using AttnoMap. We also rewrite varno so that it sees outer tuple + * (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node, AttnoMap *map) +{ + (void) expression_tree_walker(node, attno_map_walker, (void *) map); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + AttnoMap *attnomap; + ListCell *lc1, *lc2; + + if (node == NULL) + return false; + + attnomap = (AttnoMap *) context; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + var->varno = OUTER_VAR; + else + var->varno = INNER_VAR; + } + return expression_tree_walker(node, attno_map_walker, (void *) context); + } + else if (IsA(node, Var)) + { + var = (Var *)node; + + elog(DEBUG1, "original varno: %d varattno: %d", var->varno, var->varattno); + + forboth(lc1, attnomap->attno, lc2, attnomap->attnosyn) + { + int attno = lfirst_int(lc1); + int attnosyn = lfirst_int(lc2); + + elog(DEBUG1, "walker: varattno: %d varattnosyn: %d",attno, attnosyn); + if (var->varattno == attnosyn) + { + elog(DEBUG1, "loc: %d rewrite varattno from: %d to %d", var->location, attnosyn, attno); + var->varattno = attno; + } + } + } + return expression_tree_walker(node, attno_map_walker, (void *) context); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2919,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2970,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3312,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3332,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3652,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3766,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3843,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3867,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3904,400 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + appendStringInfoChar(pattern_str, vname[0]); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s quantifier: %s", vname, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList) + { + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, vname[0]); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_scantuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_outertuple = winstate->null_slot; + } + else + { + econtext->ecxt_outertuple = slot; + } + } + } + else + econtext->ecxt_outertuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..4fd3bd1a93 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,14 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2563,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Jul_26_21_21_34_2023_317)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v3-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v4 4/7] Row pattern recognition patch (executor). @ 2023-08-09 07:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-08-09 07:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 674 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + src/include/windowapi.h | 8 + 5 files changed, 732 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5354e47045 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,20 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +687,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +807,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +879,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +954,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +974,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1043,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2122,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2459,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2557,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2751,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2791,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2859,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2910,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3252,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3272,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3592,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3706,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3783,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3807,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3844,433 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Aug__9_17_41_12_2023_134)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v4-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v4 4/7] Row pattern recognition patch (executor). @ 2023-08-09 07:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-08-09 07:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 674 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + src/include/windowapi.h | 8 + 5 files changed, 732 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5354e47045 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,20 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +687,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +807,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +879,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +954,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +974,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1043,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2122,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2459,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2557,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2751,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2791,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2859,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2910,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3252,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3272,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3592,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3706,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3783,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3807,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3844,433 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Aug__9_17_41_12_2023_134)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v4-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v4 4/7] Row pattern recognition patch (executor). @ 2023-08-09 07:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-08-09 07:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 674 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + src/include/windowapi.h | 8 + 5 files changed, 732 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5354e47045 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,20 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +687,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +807,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +879,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +954,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +974,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1043,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2122,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2459,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2557,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2751,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2791,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2859,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2910,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3252,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3272,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3592,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3706,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3783,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3807,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3844,433 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Aug__9_17_41_12_2023_134)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v4-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v4 4/7] Row pattern recognition patch (executor). @ 2023-08-09 07:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-08-09 07:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 674 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + src/include/windowapi.h | 8 + 5 files changed, 732 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5354e47045 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,20 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +687,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +807,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +879,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +954,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +974,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1043,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2122,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2459,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2557,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2751,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2791,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2859,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2910,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3252,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3272,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3592,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3706,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3783,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3807,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3844,433 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Aug__9_17_41_12_2023_134)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v4-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v4 4/7] Row pattern recognition patch (executor). @ 2023-08-09 07:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-08-09 07:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 674 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + src/include/windowapi.h | 8 + 5 files changed, 732 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5354e47045 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,20 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +687,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +807,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +879,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +954,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +974,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1043,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2122,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2459,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2557,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2751,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2791,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2859,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2910,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3252,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3272,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3592,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3706,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3783,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3807,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3844,433 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Aug__9_17_41_12_2023_134)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v4-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v4 4/7] Row pattern recognition patch (executor). @ 2023-08-09 07:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-08-09 07:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 674 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + src/include/windowapi.h | 8 + 5 files changed, 732 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5354e47045 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,20 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +687,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +807,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +879,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +954,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +974,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1043,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2122,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2459,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2557,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2751,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2791,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2859,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2910,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3080,7 +3252,7 @@ are_peers(WindowAggState *winstate, TupleTableSlot *slot1, * * Returns true if successful, false if no such row */ -static bool +bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) { WindowAggState *winstate = winobj->winstate; @@ -3100,7 +3272,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3592,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3706,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3783,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3807,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3844,433 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +WindowAggState * +WinGetAggState(WindowObject winobj) +{ + return winobj->winstate; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6996073989..fa100b2665 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10397,6 +10397,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- diff --git a/src/include/windowapi.h b/src/include/windowapi.h index b8c2c565d1..1e292648e9 100644 --- a/src/include/windowapi.h +++ b/src/include/windowapi.h @@ -58,7 +58,15 @@ extern Datum WinGetFuncArgInFrame(WindowObject winobj, int argno, int relpos, int seektype, bool set_mark, bool *isnull, bool *isout); +extern int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); + extern Datum WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull); +extern WindowAggState *WinGetAggState(WindowObject winobj); + +extern bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + #endif /* WINDOWAPI_H */ -- 2.25.1 ----Next_Part(Wed_Aug__9_17_41_12_2023_134)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v4-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v5 4/7] Row pattern recognition patch (executor). @ 2023-09-02 06:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-02 06:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 671 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + 4 files changed, 722 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..2e59369a71 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,25 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +692,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +812,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +884,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +944,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +959,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +979,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1048,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2127,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2464,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2562,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2756,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2796,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2864,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2915,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3277,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3597,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3711,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3788,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3812,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3849,427 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Sep__2_15_52_35_2023_273)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v5-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v5 4/7] Row pattern recognition patch (executor). @ 2023-09-02 06:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-02 06:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 671 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + 4 files changed, 722 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..2e59369a71 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,25 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +692,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +812,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +884,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +944,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +959,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +979,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1048,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2127,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2464,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2562,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2756,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2796,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2864,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2915,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3277,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3597,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3711,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3788,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3812,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3849,427 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Sep__2_15_52_35_2023_273)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v5-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v5 4/7] Row pattern recognition patch (executor). @ 2023-09-02 06:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-02 06:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 671 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + 4 files changed, 722 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..2e59369a71 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,25 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +692,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +812,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +884,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +944,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +959,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +979,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1048,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2127,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2464,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2562,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2756,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2796,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2864,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2915,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3277,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3597,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3711,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3788,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3812,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3849,427 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Sep__2_15_52_35_2023_273)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v5-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v5 4/7] Row pattern recognition patch (executor). @ 2023-09-02 06:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-02 06:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 671 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + 4 files changed, 722 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..2e59369a71 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,25 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +692,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +812,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +884,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +944,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +959,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +979,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1048,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2127,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2464,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2562,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2756,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2796,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2864,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2915,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3277,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3597,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3711,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3788,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3812,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3849,427 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Sep__2_15_52_35_2023_273)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v5-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v5 4/7] Row pattern recognition patch (executor). @ 2023-09-02 06:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-02 06:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 671 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + 4 files changed, 722 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..2e59369a71 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,25 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +692,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +812,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +884,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +944,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +959,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +979,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1048,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2127,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2464,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2562,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2756,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2796,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2864,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2915,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3277,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3597,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3711,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3788,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3812,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3849,427 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Sep__2_15_52_35_2023_273)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v5-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v5 4/7] Row pattern recognition patch (executor). @ 2023-09-02 06:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-02 06:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 671 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 38 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 19 + 4 files changed, 722 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..2e59369a71 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,25 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +692,9 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool reduced_frame_set; + bool check_reduced_frame; + int num_rows_in_reduced_frame; numaggs = winstate->numaggs; if (numaggs == 0) @@ -790,6 +812,7 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || winstate->aggregatedupto <= winstate->frameheadpos) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +884,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -919,6 +944,10 @@ eval_windowaggregates(WindowAggState *winstate) ExecClearTuple(agg_row_slot); } + reduced_frame_set = false; + check_reduced_frame = false; + num_rows_in_reduced_frame = 0; + /* * Advance until we reach a row not in frame (or end of partition). * @@ -930,12 +959,18 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { if (!window_gettupleslot(agg_winobj, winstate->aggregatedupto, agg_row_slot)) + { + if (check_reduced_frame) + winstate->aggregatedupto--; break; /* must be end of partition */ + } } /* @@ -944,10 +979,47 @@ eval_windowaggregates(WindowAggState *winstate) */ ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) + { + if (winstate->patternVariableList != NIL && check_reduced_frame) + winstate->aggregatedupto--; break; + } if (ret == 0) goto next_tuple; + if (winstate->patternVariableList != NIL) + { + if (!reduced_frame_set) + { + num_rows_in_reduced_frame = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + reduced_frame_set = true; + elog(DEBUG1, "set num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + + if (num_rows_in_reduced_frame <= 0) + break; + + else if (num_rows_in_reduced_frame > 0) + check_reduced_frame = true; + } + + if (check_reduced_frame) + { + elog(DEBUG1, "decrease num_rows_in_reduced_frame: %d pos: " INT64_FORMAT, + num_rows_in_reduced_frame, winstate->aggregatedupto); + num_rows_in_reduced_frame--; + if (num_rows_in_reduced_frame < 0) + { + /* + * No more rows remain in the reduced frame. Finish + * accumulating row into the aggregates. + */ + winstate->aggregatedupto--; + break; + } + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1048,8 @@ next_tuple: ExecClearTuple(agg_row_slot); } + elog(DEBUG1, "===== break loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -2053,6 +2127,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2388,6 +2464,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2562,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2756,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2796,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2864,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2915,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3277,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3597,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,6 +3711,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ @@ -3565,6 +3788,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3812,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3849,427 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + if (winstate->patternVariableList == NIL) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + return 0; + } + + /* save original pos */ + original_pos = pos; + + /* + * Check whether the row speicied by pos is in the reduced frame. The + * second and subsequent rows need to be recognized as "unmatched" rows if + * AFTER MATCH SKIP PAST LAST ROW is defined. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + pos > winstate->headpos_in_reduced_frame && + pos < (winstate->headpos_in_reduced_frame + winstate->num_rows_in_reduced_frame)) + return -2; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no matches found in the first row */ + return -1; + } + + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + if (num_matched_rows <= 0) + return -1; + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + winstate->headpos_in_reduced_frame = original_pos; + winstate->num_rows_in_reduced_frame = num_matched_rows; + + return num_matched_rows; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + elog(DEBUG1, "evaluate_pattern: define variable: %s, pattern variable: %s", name, vname); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..e4cab36ec9 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,26 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..2bd6fcb5e1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2519,6 +2519,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2564,16 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* head of the reduced window frame */ + int64 headpos_in_reduced_frame; + /* number of rows in the reduced window frame */ + int64 num_rows_in_reduced_frame; } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Sep__2_15_52_35_2023_273)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v5-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v6 4/7] Row pattern recognition patch (executor). @ 2023-09-12 05:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 842 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 898 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..32270d051a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row or an unmatched row, we don't need to + * accumulate rows, just return NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + (get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED || + get_reduced_frame_map(winstate, winstate->currentpos) == RF_UNMATCHED)) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is enabled and we just return NULL. because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row or unmatched row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,561 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Sep_12_15_18_43_2023_359)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v6-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v6 4/7] Row pattern recognition patch (executor). @ 2023-09-12 05:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 842 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 898 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..32270d051a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row or an unmatched row, we don't need to + * accumulate rows, just return NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + (get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED || + get_reduced_frame_map(winstate, winstate->currentpos) == RF_UNMATCHED)) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is enabled and we just return NULL. because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row or unmatched row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,561 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Sep_12_15_18_43_2023_359)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v6-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v6 4/7] Row pattern recognition patch (executor). @ 2023-09-12 05:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 842 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 898 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..32270d051a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row or an unmatched row, we don't need to + * accumulate rows, just return NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + (get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED || + get_reduced_frame_map(winstate, winstate->currentpos) == RF_UNMATCHED)) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is enabled and we just return NULL. because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row or unmatched row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,561 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Sep_12_15_18_43_2023_359)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v6-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v6 4/7] Row pattern recognition patch (executor). @ 2023-09-12 05:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 842 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 898 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..32270d051a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row or an unmatched row, we don't need to + * accumulate rows, just return NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + (get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED || + get_reduced_frame_map(winstate, winstate->currentpos) == RF_UNMATCHED)) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is enabled and we just return NULL. because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row or unmatched row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,561 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Sep_12_15_18_43_2023_359)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v6-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v6 4/7] Row pattern recognition patch (executor). @ 2023-09-12 05:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 842 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 898 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..32270d051a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row or an unmatched row, we don't need to + * accumulate rows, just return NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + (get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED || + get_reduced_frame_map(winstate, winstate->currentpos) == RF_UNMATCHED)) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is enabled and we just return NULL. because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row or unmatched row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,561 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Sep_12_15_18_43_2023_359)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v6-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v6 4/7] Row pattern recognition patch (executor). @ 2023-09-12 05:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 842 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 898 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..32270d051a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row or an unmatched row, we don't need to + * accumulate rows, just return NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + (get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED || + get_reduced_frame_map(winstate, winstate->currentpos) == RF_UNMATCHED)) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is enabled and we just return NULL. because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row or unmatched row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,561 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Sep_12_15_18_43_2023_359)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v6-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v6 4/7] Row pattern recognition patch (executor). @ 2023-09-12 05:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-12 05:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 842 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 898 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..32270d051a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row or an unmatched row, we don't need to + * accumulate rows, just return NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + (get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED || + get_reduced_frame_map(winstate, winstate->currentpos) == RF_UNMATCHED)) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is enabled and we just return NULL. because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row or unmatched row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,561 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search set of encode_str. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, char *encoded_str, int *resultlen) +{ + char *p; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how log the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr is, it error + * out if pattern is not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + + p = str_set[set_index]->data; + while (*p) + { + encoded_str[set_index] = *p; + p++; + search_str_set_recurse(pattern, str_set, set_size, set_index + 1, encoded_str, resultlen); + } +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Sep_12_15_18_43_2023_359)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v6-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v7 4/7] Row pattern recognition patch (executor). @ 2023-09-22 04:53 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-22 04:53 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 853 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 909 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..84d1b8acaa 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + int str_index, char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,572 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform regex search pattern against encoded string array str_set. + * returns the number of longest matching rows. + * str_set: array of encoded string. Each array element corresponds to each + * row. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, 0, + encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + * + * Recurse among matched pattern variables in a row. The max recursion depth + * is number of pattern variables matched in a row. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, int str_index, + char *encoded_str, int *resultlen) +{ + for (;;) + { + char c; + + c = str_set[set_index]->data[str_index]; + if (c == '\0') + return; + encoded_str[set_index] = c; + set_index++; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + else + search_str_set_recurse(pattern, str_set, set_size, set_index, str_index + 1, + encoded_str, resultlen); + } +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Sep_22_14_16_40_2023_530)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v7-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v7 4/7] Row pattern recognition patch (executor). @ 2023-09-22 04:53 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-22 04:53 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 853 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 909 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..84d1b8acaa 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + int str_index, char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,572 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform regex search pattern against encoded string array str_set. + * returns the number of longest matching rows. + * str_set: array of encoded string. Each array element corresponds to each + * row. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, 0, + encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + * + * Recurse among matched pattern variables in a row. The max recursion depth + * is number of pattern variables matched in a row. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, int str_index, + char *encoded_str, int *resultlen) +{ + for (;;) + { + char c; + + c = str_set[set_index]->data[str_index]; + if (c == '\0') + return; + encoded_str[set_index] = c; + set_index++; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + else + search_str_set_recurse(pattern, str_set, set_size, set_index, str_index + 1, + encoded_str, resultlen); + } +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Sep_22_14_16_40_2023_530)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v7-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v7 4/7] Row pattern recognition patch (executor). @ 2023-09-22 04:53 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-22 04:53 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 853 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 909 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..84d1b8acaa 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + int str_index, char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,572 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform regex search pattern against encoded string array str_set. + * returns the number of longest matching rows. + * str_set: array of encoded string. Each array element corresponds to each + * row. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, 0, + encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + * + * Recurse among matched pattern variables in a row. The max recursion depth + * is number of pattern variables matched in a row. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, int str_index, + char *encoded_str, int *resultlen) +{ + for (;;) + { + char c; + + c = str_set[set_index]->data[str_index]; + if (c == '\0') + return; + encoded_str[set_index] = c; + set_index++; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + else + search_str_set_recurse(pattern, str_set, set_size, set_index, str_index + 1, + encoded_str, resultlen); + } +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Sep_22_14_16_40_2023_530)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v7-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v7 4/7] Row pattern recognition patch (executor). @ 2023-09-22 04:53 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-22 04:53 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 853 ++++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 909 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..84d1b8acaa 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -182,8 +184,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +198,32 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringInfo *str_set, int set_size); +static void search_str_set_recurse(char *pattern, StringInfo *str_set, int set_size, int set_index, + int str_index, char *encoded_str, int *resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); /* * initialize_windowaggregate @@ -673,6 +699,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +805,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +818,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +894,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +952,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +988,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1008,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1058,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1079,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1183,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2147,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2317,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2495,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2593,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2787,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2827,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2895,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2946,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3308,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3628,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3742,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3823,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3847,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3884,572 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + + /* + * Array of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + #define ENCODED_STR_ARRAY_ALLOC_SIZE 128 + StringInfo *str_set = NULL; + int str_set_index; + int str_set_size; + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + /* build encoded string array */ + if (str_set == NULL) + { + str_set_index = 0; + str_set_size = ENCODED_STR_ARRAY_ALLOC_SIZE * sizeof(StringInfo); + str_set = palloc(str_set_size); + } + + str_set[str_set_index++] = encoded_str; + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + if (str_set_index >= str_set_size) + { + str_set_size *= 2; + str_set = repalloc(str_set, str_set_size); + } + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (str_set == NULL) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set, str_set_index); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform regex search pattern against encoded string array str_set. + * returns the number of longest matching rows. + * str_set: array of encoded string. Each array element corresponds to each + * row. + * set_size: size of set_str array. + */ +static +int search_str_set(char *pattern, StringInfo *str_set, int set_size) +{ + char *encoded_str = palloc0(set_size+1); + int resultlen = 0; + + search_str_set_recurse(pattern, str_set, set_size, 0, 0, + encoded_str, &resultlen); + elog(DEBUG1, "search_str_set returns %d", resultlen); + return resultlen; +} + +/* + * Workhorse of search_str_set. + * + * Recurse among matched pattern variables in a row. The max recursion depth + * is number of pattern variables matched in a row. + */ +static +void search_str_set_recurse(char *pattern, StringInfo *str_set, + int set_size, int set_index, int str_index, + char *encoded_str, int *resultlen) +{ + for (;;) + { + char c; + + c = str_set[set_index]->data[str_index]; + if (c == '\0') + return; + encoded_str[set_index] = c; + set_index++; + + if (set_index >= set_size) + { + Datum d; + text *res; + char *substr; + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + int len; + + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + if (len > *resultlen) + /* remember the longest match */ + *resultlen = len; + } + } + return; + } + else + search_str_set_recurse(pattern, str_set, set_size, set_index, str_index + 1, + encoded_str, resultlen); + } +} + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Sep_22_14_16_40_2023_530)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v7-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v8 4/7] Row pattern recognition patch (executor). @ 2023-09-25 05:01 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-25 05:01 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1024 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1080 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5f2dfdf943 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2906,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2957,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3319,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3639,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3753,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3834,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3858,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3895,732 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Sep_25_14_26_30_2023_752)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v8-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v8 4/7] Row pattern recognition patch (executor). @ 2023-09-25 05:01 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-25 05:01 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1024 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1080 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5f2dfdf943 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2906,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2957,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3319,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3639,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3753,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3834,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3858,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3895,732 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Sep_25_14_26_30_2023_752)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v8-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v8 4/7] Row pattern recognition patch (executor). @ 2023-09-25 05:01 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-25 05:01 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1024 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1080 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5f2dfdf943 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2906,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2957,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3319,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3639,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3753,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3834,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3858,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3895,732 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Sep_25_14_26_30_2023_752)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v8-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v8 4/7] Row pattern recognition patch (executor). @ 2023-09-25 05:01 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-09-25 05:01 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1024 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1080 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 310ac23e3a..5f2dfdf943 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2691,6 +2906,8 @@ ExecEndWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -2740,6 +2957,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3100,7 +3319,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3420,14 +3639,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3494,11 +3753,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3565,6 +3834,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3583,15 +3858,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3622,3 +3895,732 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9805bc6118..d20f803cf5 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index cb714f4a19..63feb68f60 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2471,6 +2471,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2519,6 +2524,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2555,6 +2569,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Sep_25_14_26_30_2023_752)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v8-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v9 4/7] Row pattern recognition patch (executor). @ 2023-10-04 05:51 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-04 05:51 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1021 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1077 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..5da1bb5a6f 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2938,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3300,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3620,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3734,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3815,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3839,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3876,731 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index f0b7b9cbd8..24d288336a 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_Oct__4_15_03_28_2023_821)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v9-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v9 4/7] Row pattern recognition patch (executor). @ 2023-10-04 05:51 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-04 05:51 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1021 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1077 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..5da1bb5a6f 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2938,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3300,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3620,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3734,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3815,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3839,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3876,731 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index f0b7b9cbd8..24d288336a 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_Oct__4_15_03_28_2023_821)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v9-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v9 4/7] Row pattern recognition patch (executor). @ 2023-10-04 05:51 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-04 05:51 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1021 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1077 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..5da1bb5a6f 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2938,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3300,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3620,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3734,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3815,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3839,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3876,731 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index f0b7b9cbd8..24d288336a 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_Oct__4_15_03_28_2023_821)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v9-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v9 4/7] Row pattern recognition patch (executor). @ 2023-10-04 05:51 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-04 05:51 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1021 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1077 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..5da1bb5a6f 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,12 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +190,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +204,37 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); /* * initialize_windowaggregate @@ -673,6 +710,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +816,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +829,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +905,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +963,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +999,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1019,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1069,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1090,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1194,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2158,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2328,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2506,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2604,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2798,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2838,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2938,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3300,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3620,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3734,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3815,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3839,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3876,731 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + + /* + * Set of pattern variables evaluted to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + elog(DEBUG1, "vname: %s initial: %c quantifier: %s", vname, initial, quantifier); + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + num_matched_rows = search_str_set(pattern_str->data, str_set); + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. str_set is a set + * of StringInfo. Each StringInfo has a string comprising initial characters + * of pattern variables being true in a row. Returns the longest number of + * the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set) +{ + int set_size; /* number of rows in the set */ + int resultlen = 0; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * loop over each new pattern variable char in previous result + * char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + else + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo old = string_set_get(old_str_set, i); + + p = str->data; + + /* + * loop over each pattern variable char in the input set. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* copy source string */ + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + p++; /* next pattern variable */ + } + } + /* we no long need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + + for (index = 0; index < new_str_size; index++) + { + int len; + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no long need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern)))) > 0) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(cstring_to_text(encoded_str)), + PointerGetDatum(cstring_to_text(pattern))); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + } + } + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index f0b7b9cbd8..24d288336a 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10416,6 +10416,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_Oct__4_15_03_28_2023_821)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v9-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v10 4/7] Row pattern recognition patch (executor). @ 2023-10-22 02:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-22 02:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1363 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1419 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..2e1baef7ea 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,43 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +//static int search_str_set(char *pattern, StringSet *str_set, int *initial_orders); +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +744,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +850,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +863,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +997,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1033,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1053,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1103,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1124,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1228,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2192,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2362,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2540,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2638,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2832,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2872,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2972,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3334,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3654,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3768,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3849,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3873,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3910,1039 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + new = makeStringInfo(); + appendStringInfoString(new, old->data); + string_set_add(new_str_set, new); + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index c92d0631a0..ebb017b015 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10425,6 +10425,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sun_Oct_22_11_39_20_2023_140)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v10-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v10 4/7] Row pattern recognition patch (executor). @ 2023-10-22 02:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-22 02:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1363 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1419 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..2e1baef7ea 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,43 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +//static int search_str_set(char *pattern, StringSet *str_set, int *initial_orders); +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +744,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +850,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +863,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +997,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1033,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1053,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1103,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1124,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1228,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2192,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2362,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2540,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2638,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2832,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2872,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2972,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3334,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3654,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3768,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3849,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3873,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3910,1039 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + new = makeStringInfo(); + appendStringInfoString(new, old->data); + string_set_add(new_str_set, new); + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index c92d0631a0..ebb017b015 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10425,6 +10425,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sun_Oct_22_11_39_20_2023_140)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v10-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v10 4/7] Row pattern recognition patch (executor). @ 2023-10-22 02:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-22 02:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1363 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1419 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..2e1baef7ea 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,43 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +//static int search_str_set(char *pattern, StringSet *str_set, int *initial_orders); +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +744,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +850,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +863,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +997,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1033,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1053,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1103,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1124,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1228,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2192,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2362,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2540,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2638,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2832,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2872,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2972,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3334,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3654,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3768,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3849,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3873,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3910,1039 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + new = makeStringInfo(); + appendStringInfoString(new, old->data); + string_set_add(new_str_set, new); + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index c92d0631a0..ebb017b015 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10425,6 +10425,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sun_Oct_22_11_39_20_2023_140)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v10-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v10 4/7] Row pattern recognition patch (executor). @ 2023-10-22 02:22 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-10-22 02:22 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1363 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1419 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..2e1baef7ea 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,43 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +//static int search_str_set(char *pattern, StringSet *str_set, int *initial_orders); +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +744,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +850,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +863,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +939,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +997,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1033,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1053,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1103,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1124,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1228,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2192,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2362,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2540,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2638,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2832,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2872,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2972,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3334,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3654,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3768,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3849,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3873,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3910,1039 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + int64 result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + int64 i; + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + new = makeStringInfo(); + appendStringInfoString(new, old->data); + string_set_add(new_str_set, new); + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + pfree(str->data); + pfree(str); + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index b87a624fb2..9ebcc7b5d2 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" #include "windowapi.h" @@ -36,11 +39,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -673,7 +684,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -713,3 +724,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index c92d0631a0..ebb017b015 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10425,6 +10425,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 108d69ba28..28d098b1cf 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sun_Oct_22_11_39_20_2023_140)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v10-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v11 4/7] Row pattern recognition patch (executor). @ 2023-11-08 06:57 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-11-08 06:57 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1420 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1476 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..ea5e73c969 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +938,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +996,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1032,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1052,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1102,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1123,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1227,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2191,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2361,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2539,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2637,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2831,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2871,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2971,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3333,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3653,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3767,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3848,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3872,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3909,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 0bfbac00d7..a4a11c7f8d 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index f14aed422a..6df54a3cab 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10423,6 +10423,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 5d7f17dee0..d8f92720bc 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_Nov__8_16_37_05_2023_872)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v11-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v11 4/7] Row pattern recognition patch (executor). @ 2023-11-08 06:57 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-11-08 06:57 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1420 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1476 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..ea5e73c969 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +938,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +996,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1032,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1052,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1102,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1123,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1227,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2191,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2361,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2539,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2637,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2831,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2871,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2971,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3333,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3653,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3767,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3848,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3872,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3909,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 0bfbac00d7..a4a11c7f8d 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index f14aed422a..6df54a3cab 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10423,6 +10423,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 5d7f17dee0..d8f92720bc 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_Nov__8_16_37_05_2023_872)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v11-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v11 4/7] Row pattern recognition patch (executor). @ 2023-11-08 06:57 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-11-08 06:57 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1420 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1476 insertions(+), 13 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 77724a6daa..ea5e73c969 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -861,8 +938,10 @@ eval_windowaggregates(WindowAggState *winstate) * If we created a mark pointer for aggregates, keep it pushed up to frame * head, so that tuplestore can discard unnecessary rows. */ +#ifdef NOT_USED if (agg_winobj->markptr >= 0) WinSetMarkPosition(agg_winobj, winstate->frameheadpos); +#endif /* * Now restart the aggregates that require it. @@ -917,6 +996,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1032,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1052,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1102,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1123,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1227,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2191,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2361,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2539,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2637,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2831,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2871,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2971,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3333,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3653,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3767,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3848,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3872,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3909,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 0bfbac00d7..a4a11c7f8d 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index f14aed422a..6df54a3cab 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10423,6 +10423,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 5d7f17dee0..d8f92720bc 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_Nov__8_16_37_05_2023_872)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v11-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v12 4/7] Row pattern recognition patch (executor). @ 2023-12-04 11:23 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-12-04 11:23 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1435 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1490 insertions(+), 14 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3258305f57..a093e5dec6 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +939,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1009,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1045,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1065,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1115,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1136,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1240,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2204,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2374,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2552,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2650,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2844,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2884,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2984,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3346,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3666,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3780,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3861,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3885,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3922,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 0bfbac00d7..a4a11c7f8d 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index fb58dee3bc..aec365cf07 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10437,6 +10437,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 5d7f17dee0..d8f92720bc 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Dec__8_10_16_13_2023_489)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v12-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v12 4/7] Row pattern recognition patch (executor). @ 2023-12-04 11:23 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-12-04 11:23 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1435 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1490 insertions(+), 14 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3258305f57..a093e5dec6 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +939,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1009,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1045,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1065,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1115,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1136,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1240,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2204,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2374,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2552,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2650,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2844,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2884,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2984,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3346,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3666,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3780,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3861,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3885,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3922,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 0bfbac00d7..a4a11c7f8d 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index fb58dee3bc..aec365cf07 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10437,6 +10437,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 5d7f17dee0..d8f92720bc 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Dec__8_10_16_13_2023_489)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v12-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v12 4/7] Row pattern recognition patch (executor). @ 2023-12-04 11:23 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2023-12-04 11:23 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1435 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1490 insertions(+), 14 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3258305f57..a093e5dec6 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +939,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1009,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1045,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1065,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1115,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1136,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1240,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2204,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2374,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2552,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2650,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2844,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2884,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2984,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3346,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3666,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3780,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3861,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3885,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3922,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 0bfbac00d7..a4a11c7f8d 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index fb58dee3bc..aec365cf07 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10437,6 +10437,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 5d7f17dee0..d8f92720bc 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Dec__8_10_16_13_2023_489)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v12-0005-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v13 5/8] Row pattern recognition patch (executor). @ 2024-01-22 09:45 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-01-22 09:45 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1435 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1490 insertions(+), 14 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 62d028379b..28d1110b8a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +939,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1009,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1045,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1065,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1115,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1136,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1240,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2204,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2374,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2552,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2650,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2844,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2884,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2984,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3346,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3666,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3780,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3861,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3885,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3922,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 095de7741d..67a890f992 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index ad74e07dbb..a34ddaa385 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10452,6 +10452,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 561fdd98f1..888dad4c7d 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Jan_22_19_26_18_2024_011)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v13-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v13 5/8] Row pattern recognition patch (executor). @ 2024-01-22 09:45 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-01-22 09:45 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1435 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1490 insertions(+), 14 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 62d028379b..28d1110b8a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +939,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1009,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1045,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1065,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1115,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1136,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1240,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2204,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2374,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2552,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2650,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2844,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2884,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2984,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3346,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3666,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3780,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3861,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3885,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3922,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 095de7741d..67a890f992 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index ad74e07dbb..a34ddaa385 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10452,6 +10452,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 561fdd98f1..888dad4c7d 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Jan_22_19_26_18_2024_011)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v13-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v13 5/8] Row pattern recognition patch (executor). @ 2024-01-22 09:45 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-01-22 09:45 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1435 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 26 + 4 files changed, 1490 insertions(+), 14 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 62d028379b..28d1110b8a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,40 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet { + StringInfo *str_set; + Size set_size; /* current array allocation size in number of items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos { + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -182,8 +218,9 @@ static void begin_partition(WindowAggState *winstate); static void spool_tuples(WindowAggState *winstate, int64 pos); static void release_partition(WindowAggState *winstate); -static int row_is_in_frame(WindowAggState *winstate, int64 pos, +static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +232,42 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); -static bool window_gettupleslot(WindowObject winobj, int64 pos, - TupleTableSlot *slot); +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); +static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); + +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, int pos); +static bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, int index); +static void variable_pos_discard(VariablePos *variable_pos); /* * initialize_windowaggregate @@ -673,6 +743,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +849,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +862,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +939,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1009,29 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1045,11 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1065,28 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1115,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1136,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP + * TO PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1240,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2204,8 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT , winstate->currentpos); + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2374,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear existing + * reduced frame info so that we newly calculate the info starting from + * current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2552,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2650,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2844,39 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + + elog(DEBUG1, "defineVariable name: %s", name); + winstate->defineVariableList = lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *)expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2884,57 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *)node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible that arg type is Const? */ + var = (Var *)expr; + + if (func->funcid == F_PREV) + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +2984,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3346,7 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, pos, winobj->markpos ); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3666,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3780,21 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* RPR cares about frame head pos. Need to call update_frameheadpos */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3861,12 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3885,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3922,1097 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame according + * to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; get_reduced_frame_map(winstate,i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, state, pos); + break; + } + + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, rtn, pos); + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * Create reduced frame map + */ +static +void create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * Clear reduced frame map + */ +static +void clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * Get reduced frame map specified by pos + */ +static +int get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int str_set_index = 0; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, i; + + /* + * Set of pattern variables evaluated to true. + * Each character corresponds to pattern variable. + * Example: + * str_set[0] = "AB"; + * str_set[1] = "AC"; + * In this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. + * If it does not, we can just apply the pattern to each row. + * If it succeeds, we are done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", pos, vname); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { + elog(DEBUG1, "expression result is false or out of frame"); + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } + elog(DEBUG1, "pattern matched"); + + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. + * Loop over until none of pattern matches or encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", pos, vname, quantifier); + + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, encoded_str, &expression_result); + if (expression_result) + { + elog(DEBUG1, "expression result is true"); + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + + elog(DEBUG1, "pos: " INT64_FORMAT " str_set_index: %d encoded_str: %s", pos, str_set_index, encoded_str->data); + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", pos, encoded_str->data); + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth (lc1, winstate->patternVariableList, lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", pos, pattern_str->data); + + /* look for matching pattern variable sequence */ + elog(DEBUG1, "search_str_set started"); + num_matched_rows = search_str_set(pattern_str->data, str_set, variable_pos); + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); + + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * Perform pattern matching using pattern against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. For example, if DEFINE has variables START, UP and + * DOWN, PATTERN HAS START, UP and DOWN, then the initials in PATTERN will be + * 'a', 'b' and 'c'. + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows. + */ +static +int search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + + elog(DEBUG1, "index: %d", index); + + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size ; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { + elog(DEBUG1, "discard this old set because shorter match: %s", old->data); + continue; + } + + elog(DEBUG1, "keep this old set: %s", old->data); + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { + elog(DEBUG1, "discard this old set: %s", old->data); + continue; + } + + elog(DEBUG1, "str->data: %s", str->data); + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + elog(DEBUG1, "discard this new data: %s", + new->data); + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed + * entries that have shorter match length. + * Mark them as "discard" so that they are + * discarded in the next round. + */ + + /* new_index_size should be the one before */ + new_str_size = string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* mark this set to discard in the next round */ + appendStringInfoChar(new, DISCARD_CHAR); + elog(DEBUG1, "add discard char: %s", new->data); + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + elog(DEBUG1, "new_str_size: %d", new_str_size); + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + + elog(DEBUG1, "target string: %s", s->data); + + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the + * matched string is. That is the number of rows in the reduced window + * frame. The reason why we can't call textregexsubstr in the first + * place is, it errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll(regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + + +/* + * Evaluate expression associated with PATTERN variable vname. + * relpos is relative row position in a frame (starting from 0). + * "quantifier" is the quatifier part of the PATTERN regular expression. + * Currently only '+' is allowed. + * result is out paramater representing the expression evaluation result + * is true of false. + * Return values are: + * >=0: the last match absolute row position + * other wise out of frame. + */ +static +int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, *lc2, *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree (lc1, winstate->defineVariableList, lc2, winstate->defineClauseList, lc3, winstate->defineInitial) + { + char initial; + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, vname, current_pos); + *result = false; + } + else + { + /* expression is true */ + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, vname, current_pos); + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, current_pos); + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, current_pos); + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, current_pos - 1); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, current_pos - 1); + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, current_pos + 1); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, current_pos + 1); + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, *lc2; + + forboth (lc1, winstate->defineVariableList, lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet *string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * Add StringInfo str to StringSet string_set. + */ +static +void string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 ||index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * Returns the size of StringSet. + */ +static +int string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * Create and initialize variable postion structure + */ +static +VariablePos *variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * Returns true if initial1 can be followed by initial2 + */ +static +bool variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, index2; + int pos1, pos2; + + for (index1 = 0; ; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0; ; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * Discard VariablePos + */ +static +void variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 095de7741d..67a890f992 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index ad74e07dbb..a34ddaa385 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10452,6 +10452,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 561fdd98f1..888dad4c7d 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2470,6 +2470,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2518,6 +2523,15 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2554,6 +2568,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Jan_22_19_26_18_2024_011)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v13-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v14 5/8] Row pattern recognition patch (executor). @ 2024-02-28 13:59 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-02-28 13:59 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 62d028379b..c473cbd218 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2668,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 095de7741d..c5bd28ce19 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9c120fc2b7..81e4580b13 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10456,6 +10456,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 444a5f0fd5..15d8ac4c1e 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2477,6 +2477,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2525,6 +2530,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2561,6 +2579,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Feb_29_09_19_54_2024_640)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v14-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v14 5/8] Row pattern recognition patch (executor). @ 2024-02-28 13:59 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-02-28 13:59 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 62d028379b..c473cbd218 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2668,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 095de7741d..c5bd28ce19 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9c120fc2b7..81e4580b13 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10456,6 +10456,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 444a5f0fd5..15d8ac4c1e 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2477,6 +2477,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2525,6 +2530,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2561,6 +2579,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Feb_29_09_19_54_2024_640)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v14-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v14 5/8] Row pattern recognition patch (executor). @ 2024-02-28 13:59 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-02-28 13:59 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 62d028379b..c473cbd218 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2483,6 +2668,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 095de7741d..c5bd28ce19 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/builtins.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 9c120fc2b7..81e4580b13 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10456,6 +10456,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 444a5f0fd5..15d8ac4c1e 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2477,6 +2477,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2525,6 +2530,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2561,6 +2579,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Feb_29_09_19_54_2024_640)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v14-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v15 5/8] Row pattern recognition patch (executor). @ 2024-03-28 10:30 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-03-28 10:30 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 07023ee61d..b9d171e327 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10474,6 +10474,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1774c56ae3..f2322ace6f 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2549,6 +2549,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2597,6 +2602,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2633,6 +2651,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Mar_28_19_59_25_2024_076)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v15-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v15 5/8] Row pattern recognition patch (executor). @ 2024-03-28 10:30 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-03-28 10:30 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 07023ee61d..b9d171e327 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10474,6 +10474,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1774c56ae3..f2322ace6f 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2549,6 +2549,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2597,6 +2602,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2633,6 +2651,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Mar_28_19_59_25_2024_076)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v15-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v15 5/8] Row pattern recognition patch (executor). @ 2024-03-28 10:30 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-03-28 10:30 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 07023ee61d..b9d171e327 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10474,6 +10474,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1774c56ae3..f2322ace6f 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2549,6 +2549,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2597,6 +2602,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2633,6 +2651,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Mar_28_19_59_25_2024_076)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v15-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v15 5/8] Row pattern recognition patch (executor). @ 2024-03-28 10:30 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-03-28 10:30 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 07023ee61d..b9d171e327 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10474,6 +10474,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1774c56ae3..f2322ace6f 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2549,6 +2549,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2597,6 +2602,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2633,6 +2651,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Mar_28_19_59_25_2024_076)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v15-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v15 5/8] Row pattern recognition patch (executor). @ 2024-03-28 10:30 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-03-28 10:30 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 07023ee61d..b9d171e327 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10474,6 +10474,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1774c56ae3..f2322ace6f 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2549,6 +2549,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2597,6 +2602,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2633,6 +2651,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Mar_28_19_59_25_2024_076)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v15-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v16 5/8] Row pattern recognition patch (executor). @ 2024-04-12 06:49 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-04-12 06:49 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index fa2f70b7a4..053ad1764c 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Apr_12_16_09_08_2024_262)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v16-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v16 5/8] Row pattern recognition patch (executor). @ 2024-04-12 06:49 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-04-12 06:49 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index fa2f70b7a4..053ad1764c 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Apr_12_16_09_08_2024_262)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v16-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v16 5/8] Row pattern recognition patch (executor). @ 2024-04-12 06:49 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-04-12 06:49 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1617 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1679 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..9606e7d463 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -673,6 +752,7 @@ eval_windowaggregates(WindowAggState *winstate) WindowObject agg_winobj; TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot; + bool agg_result_isnull; numaggs = winstate->numaggs; if (numaggs == 0) @@ -778,6 +858,9 @@ eval_windowaggregates(WindowAggState *winstate) * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * + * - if RPR is enabled and skip mode is SKIP TO NEXT ROW, + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,8 +871,11 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + (rpr_is_defined(winstate) && + winstate->rpSkipTo == ST_NEXT_ROW)) { + elog(DEBUG1, "peraggstate->restart is set"); peraggstate->restart = true; numaggs_restart++; } @@ -862,7 +948,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1018,30 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; + } + + agg_result_isnull = false; + /* RPR is defined? */ + if (rpr_is_defined(winstate)) + { + /* + * If the skip mode is SKIP TO PAST LAST ROW and we already know that + * current row is a skipped row, we don't need to accumulate rows, + * just return NULL. Note that for unamtched row, we need to do + * aggregation so that count(*) shows 0, rather than NULL. + */ + if (winstate->rpSkipTo == ST_PAST_LAST_ROW && + get_reduced_frame_map(winstate, + winstate->currentpos) == RF_SKIPPED) + agg_result_isnull = true; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; + elog(DEBUG1, "===== loop in frame starts: " INT64_FORMAT, + winstate->aggregatedupto); + + if (agg_result_isnull) + break; + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,32 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -996,6 +1151,16 @@ next_tuple: peraggstate, result, isnull); + /* + * RPR is defined and we just return NULL because skip mode is SKIP TO + * PAST LAST ROW and current row is skipped row. + */ + if (agg_result_isnull) + { + *isnull = true; + *result = (Datum) 0; + } + /* * save the result in case next row shares the same frame. * @@ -1090,6 +1255,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2219,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2392,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2570,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2671,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2862,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2906,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3013,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3375,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3696,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3810,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3895,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3921,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3958,1249 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index fa2f70b7a4..053ad1764c 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Apr_12_16_09_08_2024_262)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v16-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v17 5/8] Row pattern recognition patch (executor). @ 2024-04-28 11:00 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-04-28 11:00 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index d927ac44a8..971d8682b1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2550,6 +2550,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2598,6 +2603,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2634,6 +2652,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sun_Apr_28_20_28_26_2024_444)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v17-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v17 5/8] Row pattern recognition patch (executor). @ 2024-04-28 11:00 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-04-28 11:00 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index d927ac44a8..971d8682b1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2550,6 +2550,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2598,6 +2603,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2634,6 +2652,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sun_Apr_28_20_28_26_2024_444)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v17-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v17 5/8] Row pattern recognition patch (executor). @ 2024-04-28 11:00 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-04-28 11:00 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index d927ac44a8..971d8682b1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2550,6 +2550,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2598,6 +2603,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2634,6 +2652,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sun_Apr_28_20_28_26_2024_444)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v17-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v18 5/8] Row pattern recognition patch (executor). @ 2024-05-11 07:11 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-11 07:11 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_May_11_16_23_07_2024_789)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v18-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v18 5/8] Row pattern recognition patch (executor). @ 2024-05-11 07:11 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-11 07:11 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_May_11_16_23_07_2024_789)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v18-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v18 5/8] Row pattern recognition patch (executor). @ 2024-05-11 07:11 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-11 07:11 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 134e3b22fd..5f7fb538f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10477,6 +10477,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_May_11_16_23_07_2024_789)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v18-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v19 5/8] Row pattern recognition patch (executor). @ 2024-05-14 23:26 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-14 23:26 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2a9f2105b1..595ef7502e 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10479,6 +10479,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_May_15_09_02_03_2024_008)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v19-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v19 5/8] Row pattern recognition patch (executor). @ 2024-05-14 23:26 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-14 23:26 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2a9f2105b1..595ef7502e 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10479,6 +10479,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_May_15_09_02_03_2024_008)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v19-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v19 5/8] Row pattern recognition patch (executor). @ 2024-05-14 23:26 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-14 23:26 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2a9f2105b1..595ef7502e 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10479,6 +10479,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Wed_May_15_09_02_03_2024_008)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v19-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v20 5/8] Row pattern recognition patch (executor). @ 2024-05-24 02:26 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-24 02:26 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6a5476d3c4..5e7506dabb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10479,6 +10479,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_May_24_11_39_19_2024_763)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v20-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v20 5/8] Row pattern recognition patch (executor). @ 2024-05-24 02:26 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-24 02:26 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6a5476d3c4..5e7506dabb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10479,6 +10479,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_May_24_11_39_19_2024_763)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v20-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v20 5/8] Row pattern recognition patch (executor). @ 2024-05-24 02:26 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-05-24 02:26 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 6a5476d3c4..5e7506dabb 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10479,6 +10479,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 8bc421e7c0..4dd9a17eca 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2554,6 +2554,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2602,6 +2607,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2638,6 +2656,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_May_24_11_39_19_2024_763)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v20-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v21 5/8] Row pattern recognition patch (executor). @ 2024-08-26 04:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-08-26 04:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 4abc6d9526..c3fafed291 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10549,6 +10549,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index af7d8fd1e7..609b066845 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2578,6 +2578,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2626,6 +2631,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2662,6 +2680,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Aug_26_13_39_47_2024_878)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v21-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v21 5/8] Row pattern recognition patch (executor). @ 2024-08-26 04:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-08-26 04:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 4abc6d9526..c3fafed291 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10549,6 +10549,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index af7d8fd1e7..609b066845 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2578,6 +2578,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2626,6 +2631,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2662,6 +2680,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Aug_26_13_39_47_2024_878)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v21-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v21 5/8] Row pattern recognition patch (executor). @ 2024-08-26 04:32 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-08-26 04:32 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 3221fa1522..140bb3941e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1090,6 +1244,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2053,6 +2208,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2221,6 +2381,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2388,6 +2559,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2486,6 +2660,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2667,6 +2851,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2674,6 +2895,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2723,6 +3002,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3083,7 +3364,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3403,14 +3685,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3477,11 +3799,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3548,6 +3884,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3566,15 +3910,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3605,3 +3947,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 4abc6d9526..c3fafed291 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10549,6 +10549,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index af7d8fd1e7..609b066845 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2578,6 +2578,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2626,6 +2631,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2662,6 +2680,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Aug_26_13_39_47_2024_878)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v21-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v22 5/8] Row pattern recognition patch (executor). @ 2024-09-19 04:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-09-19 04:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 51a6708a39..e46a3dd1b7 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1199,6 +1353,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2325,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2438,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2445,6 +2616,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2543,6 +2717,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2724,6 +2908,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2732,6 +2953,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2789,6 +3068,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3149,7 +3430,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3469,14 +3751,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3543,11 +3865,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3614,6 +3950,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3632,15 +3976,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3671,3 +4013,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 43f608d7a0..6a301920f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10604,6 +10604,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 88467977f8..058cef2121 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2581,6 +2581,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2640,6 +2645,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2667,6 +2685,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Sep_19_13_59_47_2024_608)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v22-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v22 5/8] Row pattern recognition patch (executor). @ 2024-09-19 04:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-09-19 04:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 51a6708a39..e46a3dd1b7 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1199,6 +1353,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2325,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2438,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2445,6 +2616,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2543,6 +2717,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2724,6 +2908,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2732,6 +2953,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2789,6 +3068,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3149,7 +3430,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3469,14 +3751,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3543,11 +3865,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3614,6 +3950,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3632,15 +3976,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3671,3 +4013,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 43f608d7a0..6a301920f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10604,6 +10604,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 88467977f8..058cef2121 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2581,6 +2581,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2640,6 +2645,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2667,6 +2685,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Sep_19_13_59_47_2024_608)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v22-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v22 5/8] Row pattern recognition patch (executor). @ 2024-09-19 04:48 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-09-19 04:48 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1671 insertions(+), 12 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 51a6708a39..e46a3dd1b7 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); /* * initialize_windowaggregate @@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1130,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -995,7 +1150,6 @@ next_tuple: &winstate->perfunc[wfuncno], peraggstate, result, isnull); - /* * save the result in case next row shares the same frame. * @@ -1199,6 +1353,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2325,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2438,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2445,6 +2616,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2543,6 +2717,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2724,6 +2908,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2732,6 +2953,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var node that is the argument of PREV/NET so that it sees + * scan tuple (PREV) or inner tuple (NEXT). + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + Expr *expr; + Var *var; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* sanity check */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + expr = (Expr *) lfirst(list_head(func->args)); + if (!IsA(expr, Var)) + elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible + * that arg type is + * Const? */ + var = (Var *) expr; + + if (func->funcid == F_PREV) + + /* + * Rewrite varno from OUTER_VAR to regular var no so that the + * var references scan tuple. + */ + var->varno = var->varnosyn; + else + var->varno = INNER_VAR; + +#ifdef RPR_DEBUG + elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno); +#endif + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2789,6 +3068,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3149,7 +3430,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3469,14 +3751,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3543,11 +3865,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3614,6 +3950,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3632,15 +3976,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3671,3 +4013,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0 || pos >= winstate->alloc_sz) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 43f608d7a0..6a301920f9 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10604,6 +10604,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '6122', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '6123', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 88467977f8..058cef2121 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2581,6 +2581,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2640,6 +2645,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2667,6 +2685,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Sep_19_13_59_47_2024_608)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v22-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v23 5/8] Row pattern recognition patch (executor). @ 2024-10-25 03:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-10-25 03:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1676 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1738 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 51a6708a39..e6f4fc1a7a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,53 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +233,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +245,51 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +866,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +882,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +957,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1027,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1048,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1069,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1144,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1368,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2340,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2453,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2445,6 +2631,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2543,6 +2732,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2724,6 +2923,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2732,6 +2968,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2789,6 +3130,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3149,7 +3492,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3469,14 +3813,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3543,11 +3927,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3614,6 +4012,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3632,15 +4038,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3671,3 +4075,1257 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 1ec0d6f6b5..754e855552 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10635,6 +10635,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index e4698a28c4..9a2f8254d1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2589,6 +2589,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2648,6 +2653,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2675,6 +2693,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Oct_25_13_04_53_2024_648)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v23-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v23 5/8] Row pattern recognition patch (executor). @ 2024-10-25 03:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-10-25 03:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1676 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1738 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 51a6708a39..e6f4fc1a7a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,53 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +233,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +245,51 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +866,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +882,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +957,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1027,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1048,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1069,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1144,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1368,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2340,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2453,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2445,6 +2631,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2543,6 +2732,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2724,6 +2923,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2732,6 +2968,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2789,6 +3130,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3149,7 +3492,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3469,14 +3813,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3543,11 +3927,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3614,6 +4012,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3632,15 +4038,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3671,3 +4075,1257 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 1ec0d6f6b5..754e855552 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10635,6 +10635,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index e4698a28c4..9a2f8254d1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2589,6 +2589,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2648,6 +2653,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2675,6 +2693,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Oct_25_13_04_53_2024_648)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v23-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v23 5/8] Row pattern recognition patch (executor). @ 2024-10-25 03:56 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-10-25 03:56 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1676 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1738 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 51a6708a39..e6f4fc1a7a 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +49,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +161,53 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +233,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +245,51 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +866,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +882,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +957,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1027,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1048,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1069,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1144,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1368,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2340,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2453,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2445,6 +2631,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2543,6 +2732,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2724,6 +2923,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2732,6 +2968,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2789,6 +3130,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3149,7 +3492,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3469,14 +3813,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3543,11 +3927,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3614,6 +4012,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3632,15 +4038,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3671,3 +4075,1257 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chace to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + len = do_pattern_match(pattern, s->data); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + Datum d; + text *res; + char *substr; + int len = 0; + text *pattern_text, + *encoded_str_text; + + pattern_text = cstring_to_text(pattern); + encoded_str_text = cstring_to_text(encoded_str); + + /* + * We first perform pattern matching using regexp_instr, then call + * textregexsubstr to get matched substring to know how long the matched + * string is. That is the number of rows in the reduced window frame. The + * reason why we can't call textregexsubstr in the first place is, it + * errors out if pattern does not match. + */ + if (DatumGetInt32(DirectFunctionCall2Coll( + regexp_instr, DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)))) + { + d = DirectFunctionCall2Coll(textregexsubstr, + DEFAULT_COLLATION_OID, + PointerGetDatum(encoded_str_text), + PointerGetDatum(pattern_text)); + if (d != 0) + { + res = DatumGetTextPP(d); + substr = text_to_cstring(res); + len = strlen(substr); + pfree(substr); + } + } + pfree(encoded_str_text); + pfree(pattern_text); + + return len; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 1ec0d6f6b5..754e855552 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10635,6 +10635,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index e4698a28c4..9a2f8254d1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2589,6 +2589,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2648,6 +2653,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2675,6 +2693,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Fri_Oct_25_13_04_53_2024_648)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v23-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v24 5/8] Row pattern recognition patch (executor). @ 2024-12-19 06:06 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-19 06:06 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1697 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1759 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..3c2e95f46e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -33,9 +33,13 @@ */ #include "postgres.h" +#include <regex.h> +#include <sys/types.h> + #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +52,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +164,58 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + +/* + * Regular expression compiled cache for do_pattern_match exists + */ +static regex_t *regcache = NULL; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +241,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +253,52 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); +static void do_pattern_match_finish(void); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +875,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +891,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +966,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1036,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1057,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1078,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1153,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1377,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2349,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2462,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2639,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2740,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2931,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2976,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3138,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3500,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3821,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3935,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4020,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4046,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4083,1269 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chance to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + + /* + * If the string is already freeze, we don't need to check it by + * do_pattern_match because it has been ready checked. + */ + if (s->data[s->len] == FREEZED_CHAR) + len = s->len - 1; + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + else if (s->data[s->len] == DISCARD_CHAR) + continue; + + else + len = do_pattern_match(pattern, s->data); + + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + do_pattern_match_finish(); + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + static regex_t preg; + int len; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + + /* + * Compile regexp if it does not exist. + */ + if (regcache == NULL) + { + if (regcomp(&preg, pattern, cflags)) + { + elog(ERROR, "failed to compile pattern: %s", pattern); + } + regcache = &preg; + } + + if (regexec(&preg, encoded_str, nmatch, pmatch, eflags)) + return 0; /* does not match */ + + len = pmatch[0].rm_eo; /* return match length */ + return len; +} + +static +void +do_pattern_match_finish(void) +{ + if (regcache != NULL) + regfree(regcache); + regcache = NULL; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 0f22c21723..87b2c1557f 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10651,6 +10651,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 7f71b7625d..a8e2404f83 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2587,6 +2587,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2646,6 +2651,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2673,6 +2691,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Dec_19_15_19_50_2024_894)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v24-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v24 5/8] Row pattern recognition patch (executor). @ 2024-12-19 06:06 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-19 06:06 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1697 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1759 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..3c2e95f46e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -33,9 +33,13 @@ */ #include "postgres.h" +#include <regex.h> +#include <sys/types.h> + #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +52,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +164,58 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + +/* + * Regular expression compiled cache for do_pattern_match exists + */ +static regex_t *regcache = NULL; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +241,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +253,52 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); +static void do_pattern_match_finish(void); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +875,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +891,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +966,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1036,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1057,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1078,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1153,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1377,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2349,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2462,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2639,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2740,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2931,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2976,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3138,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3500,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3821,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3935,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4020,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4046,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4083,1269 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chance to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + + /* + * If the string is already freeze, we don't need to check it by + * do_pattern_match because it has been ready checked. + */ + if (s->data[s->len] == FREEZED_CHAR) + len = s->len - 1; + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + else if (s->data[s->len] == DISCARD_CHAR) + continue; + + else + len = do_pattern_match(pattern, s->data); + + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + do_pattern_match_finish(); + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + static regex_t preg; + int len; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + + /* + * Compile regexp if it does not exist. + */ + if (regcache == NULL) + { + if (regcomp(&preg, pattern, cflags)) + { + elog(ERROR, "failed to compile pattern: %s", pattern); + } + regcache = &preg; + } + + if (regexec(&preg, encoded_str, nmatch, pmatch, eflags)) + return 0; /* does not match */ + + len = pmatch[0].rm_eo; /* return match length */ + return len; +} + +static +void +do_pattern_match_finish(void) +{ + if (regcache != NULL) + regfree(regcache); + regcache = NULL; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 0f22c21723..87b2c1557f 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10651,6 +10651,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 7f71b7625d..a8e2404f83 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2587,6 +2587,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2646,6 +2651,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2673,6 +2691,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Dec_19_15_19_50_2024_894)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v24-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v24 5/8] Row pattern recognition patch (executor). @ 2024-12-19 06:06 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-19 06:06 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1697 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1759 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..3c2e95f46e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -33,9 +33,13 @@ */ #include "postgres.h" +#include <regex.h> +#include <sys/types.h> + #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -48,6 +52,7 @@ #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +164,58 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + +/* + * Regular expression compiled cache for do_pattern_match exists + */ +static regex_t *regcache = NULL; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +241,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +253,52 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet * str_set, + VariablePos * variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str); +static void do_pattern_match_finish(void); + +static StringSet * string_set_init(void); +static void string_set_add(StringSet * string_set, StringInfo str); +static StringInfo string_set_get(StringSet * string_set, int index); +static int string_set_get_size(StringSet * string_set); +static void string_set_discard(StringSet * string_set); +static VariablePos * variable_pos_init(void); +static void variable_pos_register(VariablePos * variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos * variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos * variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos * variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +875,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +891,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +966,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1036,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1057,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1078,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1153,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1377,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2349,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2462,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2639,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2740,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2931,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2976,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3138,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3500,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3821,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3935,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4020,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4046,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4083,1269 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str = makeStringInfo(); + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chance to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + pfree(new->data); + pfree(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + + /* + * If the string is already freeze, we don't need to check it by + * do_pattern_match because it has been ready checked. + */ + if (s->data[s->len] == FREEZED_CHAR) + len = s->len - 1; + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + else if (s->data[s->len] == DISCARD_CHAR) + continue; + + else + len = do_pattern_match(pattern, s->data); + + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + do_pattern_match_finish(); + return resultlen; +} + +/* + * do_pattern_match + * perform pattern match using pattern against encoded_str. + * returns matching number of rows if matching is succeeded. + * Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str) +{ + static regex_t preg; + int len; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + + /* + * Compile regexp if it does not exist. + */ + if (regcache == NULL) + { + if (regcomp(&preg, pattern, cflags)) + { + elog(ERROR, "failed to compile pattern: %s", pattern); + } + regcache = &preg; + } + + if (regexec(&preg, encoded_str, nmatch, pmatch, eflags)) + return 0; /* does not match */ + + len = pmatch[0].rm_eo; /* return match length */ + return len; +} + +static +void +do_pattern_match_finish(void) +{ + if (regcache != NULL) + regfree(regcache); + regcache = NULL; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet * string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet * string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet * string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet * string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + { + pfree(str->data); + pfree(str); + } + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos * variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos * variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos * variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..92c528d38c 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 0f22c21723..87b2c1557f 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10651,6 +10651,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 7f71b7625d..a8e2404f83 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2587,6 +2587,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2646,6 +2651,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2673,6 +2691,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Thu_Dec_19_15_19_50_2024_894)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v24-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v25 5/9] Row pattern recognition patch (executor). @ 2024-12-21 06:19 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-21 06:19 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1745 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1807 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..2148d4ed1e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,58 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + +/* + * Regular expression compiled cache for do_pattern_match exists + */ +static regex_t *regcache = NULL; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +239,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +251,52 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, + VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); +static void do_pattern_match_finish(void); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos *variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +873,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +889,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +964,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1034,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1151,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1375,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2347,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2460,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2637,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2738,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2929,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2974,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3136,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3498,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3819,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3933,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4018,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4044,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4081,1319 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str; + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + destroyStringInfo(pattern_str); + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chance to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + destroyStringInfo(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data, old->len); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + + /* + * If the string is already freeze, we don't need to check it by + * do_pattern_match because it has been ready checked. + */ + if (s->data[s->len] == FREEZED_CHAR) + len = s->len - 1; + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + else if (s->data[s->len] == DISCARD_CHAR) + continue; + + else + len = do_pattern_match(pattern, s->data, s->len); + + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + do_pattern_match_finish(); + return resultlen; +} + +/* + * do_pattern_match perform pattern match using pattern against encoded_str + * whose length is len bytes (without null terminate). returns matching + * number of rows if matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t preg; + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + + /* + * Compile regexp if it does not exist. + */ + if (regcache == NULL) + { + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + regcache = &preg; + } + + data = (pg_wchar *) palloc((strlen(encoded_str) + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +static +void +do_pattern_match_finish(void) +{ + if (regcache != NULL) + pg_regfree(regcache); + regcache = NULL; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 79d5e96021..87591a8d43 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2649,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2689,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Dec_21_18_20_04_2024_526)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v25-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v25 5/9] Row pattern recognition patch (executor). @ 2024-12-21 06:19 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-21 06:19 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1745 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1807 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..2148d4ed1e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,58 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + +/* + * Regular expression compiled cache for do_pattern_match exists + */ +static regex_t *regcache = NULL; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +239,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +251,52 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, + VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); +static void do_pattern_match_finish(void); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos *variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +873,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +889,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +964,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1034,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1151,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1375,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2347,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2460,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2637,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2738,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2929,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2974,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3136,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3498,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3819,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3933,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4018,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4044,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4081,1319 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str; + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + destroyStringInfo(pattern_str); + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chance to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + destroyStringInfo(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data, old->len); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + + /* + * If the string is already freeze, we don't need to check it by + * do_pattern_match because it has been ready checked. + */ + if (s->data[s->len] == FREEZED_CHAR) + len = s->len - 1; + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + else if (s->data[s->len] == DISCARD_CHAR) + continue; + + else + len = do_pattern_match(pattern, s->data, s->len); + + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + do_pattern_match_finish(); + return resultlen; +} + +/* + * do_pattern_match perform pattern match using pattern against encoded_str + * whose length is len bytes (without null terminate). returns matching + * number of rows if matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t preg; + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + + /* + * Compile regexp if it does not exist. + */ + if (regcache == NULL) + { + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + regcache = &preg; + } + + data = (pg_wchar *) palloc((strlen(encoded_str) + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +static +void +do_pattern_match_finish(void) +{ + if (regcache != NULL) + pg_regfree(regcache); + regcache = NULL; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 79d5e96021..87591a8d43 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2649,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2689,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Dec_21_18_20_04_2024_526)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v25-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v25 5/9] Row pattern recognition patch (executor). @ 2024-12-21 06:19 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-21 06:19 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1745 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 30 + 4 files changed, 1807 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..2148d4ed1e 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,58 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ +} StringSet; + +/* + * Allowed subsequent PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */ +} VariablePos; + +/* + * Regular expression compiled cache for do_pattern_match exists + */ +static regex_t *regcache = NULL; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +239,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +251,52 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(char *pattern, StringSet *str_set, + VariablePos *variable_pos); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); +static void do_pattern_match_finish(void); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str); +static StringInfo string_set_get(StringSet *string_set, int index); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static void variable_pos_discard(VariablePos *variable_pos); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +873,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +889,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +964,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1034,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1055,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1076,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, + winstate->currentpos) != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1151,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1375,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2347,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2460,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2637,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2738,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2929,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2974,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3136,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3498,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3819,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3933,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4018,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4044,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4081,1319 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringInfo pattern_str; + StringSet *str_set; + int initial_index; + VariablePos *variable_pos; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + encoded_str = makeStringInfo(); + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* build regular expression */ + pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + initial_index = 0; + + variable_pos = variable_pos_init(); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s", + pos, pattern_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(pattern_str->data, + str_set, variable_pos); +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + variable_pos_discard(variable_pos); + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + destroyStringInfo(pattern_str); + + return; +} + +/* + * search_str_set + * Perform pattern matching using "pattern" against str_set. pattern is a + * regular expression derived from PATTERN clause. Note that the regular + * expression string is prefixed by '^' and followed by initials represented + * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo + * has a string comprising initials of pattern variable strings being true in + * a row. The initials are one of [a-y], parallel to the order of variable + * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If + * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a', + * 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(char *pattern, StringSet *str_set, VariablePos *variable_pos) +{ +#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */ +#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the + * char */ +#define DISCARD_CHAR 'z' /* a pattern is not need to keep */ + + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *old_str_set, + *new_str_set; + int new_str_size; + int len; + + set_size = string_set_get_size(str_set); + new_str_set = string_set_init(); + len = 0; + resultlen = 0; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size); +#endif + for (index = 0; index < set_size; index++) + { + StringInfo str; /* search target row */ + char *p; + int old_set_size; + int i; + +#ifdef RPR_DEBUG + elog(DEBUG1, "index: %d", index); +#endif + if (index == 0) + { + /* copy variables in row 0 */ + str = string_set_get(str_set, index); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: NULL new_str: %s", new->data); +#endif + p++; /* next pattern variable */ + } + } + else /* index != 0 */ + { + old_str_set = new_str_set; + new_str_set = string_set_init(); + str = string_set_get(str_set, index); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each rows in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + StringInfo new; + char last_old_char; + int old_str_len; + StringInfo old = string_set_get(old_str_set, i); + + p = old->data; + old_str_len = strlen(p); + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Is this old set freezed? */ + if (last_old_char == FREEZED_CHAR) + { + /* if shorter match. we can discard it */ + if ((old_str_len - 1) < resultlen) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set because shorter match: %s", + old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "keep this old set: %s", old->data); +#endif + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old); + old_str_set->str_set[i] = NULL; + continue; + } + /* Can this old set be discarded? */ + else if (last_old_char == DISCARD_CHAR) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this old set: %s", old->data); +#endif + continue; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "str->data: %s", str->data); +#endif + + /* + * loop over each pattern variable initial char in the input + * set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable + * initial character position is greater than or equal to + * the old set's last pattern variable initial character + * position. For example, if the old set's last pattern + * variable initials are "ab", then the new pattern + * variable initial can be "b" or "c" but can not be "a", + * if the initials in PATTERN is something like "a b c" or + * "a b+ c+" etc. This optimization is possible when we + * only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + { + /* copy source string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add pattern variable char */ + appendStringInfoChar(new, *p); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", + old->data, new->data); +#endif + + /* + * Adhoc optimization. If the first letter in the + * input string is the first and second position one + * and there's no associated quatifier '+', then we + * can dicard the input because there's no chance to + * expand the string further. + * + * For example, pattern "abc" cannot match "aa". + */ +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c", + pattern[1], pattern[2], new->data[0], new->data[1]); +#endif + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "discard this new data: %s", + new->data); +#endif + destroyStringInfo(new); + continue; + } + + /* add new one to string set */ + string_set_add(new_str_set, new); + } + else + { + /* + * We are freezing this pattern string. Since there's + * no chance to expand the string further, we perform + * pattern matching against the string. If it does not + * match, we can discard it. + */ + len = do_pattern_match(pattern, old->data, old->len); + + if (len <= 0) + { + /* no match. we can discard it */ + continue; + } + + else if (len <= resultlen) + { + /* shorter match. we can discard it */ + continue; + } + else + { + /* match length is the longest so far */ + + int new_index; + + /* remember the longest match */ + resultlen = len; + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* add freezed mark */ + appendStringInfoChar(new, FREEZED_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data); +#endif + string_set_add(new_str_set, new); + + /* + * Search new_str_set to find out freezed entries + * that have shorter match length. Mark them as + * "discard" so that they are discarded in the + * next round. + */ + + /* new_index_size should be the one before */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; + new_index++) + { + char new_last_char; + int new_str_len; + + new = string_set_get(new_str_set, new_index); + new_str_len = strlen(new->data); + if (new_str_len > 0) + { + new_last_char = + new->data[new_str_len - 1]; + if (new_last_char == FREEZED_CHAR && + (new_str_len - 1) <= len) + { + /* + * mark this set to discard in the + * next round + */ + appendStringInfoChar(new, DISCARD_CHAR); +#ifdef RPR_DEBUG + elog(DEBUG1, "add discard char: %s", new->data); +#endif + } + } + } + } + } + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + } + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); +#ifdef RPR_DEBUG + elog(DEBUG1, "new_str_size: %d", new_str_size); +#endif + len = 0; + resultlen = 0; + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index); + if (s == NULL) + continue; /* no data */ + +#ifdef RPR_DEBUG + elog(DEBUG1, "target string: %s", s->data); +#endif + + /* + * If the string is already freeze, we don't need to check it by + * do_pattern_match because it has been ready checked. + */ + if (s->data[s->len] == FREEZED_CHAR) + len = s->len - 1; + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + else if (s->data[s->len] == DISCARD_CHAR) + continue; + + else + len = do_pattern_match(pattern, s->data, s->len); + + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + do_pattern_match_finish(); + return resultlen; +} + +/* + * do_pattern_match perform pattern match using pattern against encoded_str + * whose length is len bytes (without null terminate). returns matching + * number of rows if matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t preg; + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + + /* + * Compile regexp if it does not exist. + */ + if (regcache == NULL) + { + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + regcache = &preg; + } + + data = (pg_wchar *) palloc((strlen(encoded_str) + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +static +void +do_pattern_match_finish(void) +{ + if (regcache != NULL) + pg_regfree(regcache); + regcache = NULL; +} + +/* + * evaluate_pattern + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str) +{ + Size set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->set_size = set_size; + } + + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_discard + * Discard VariablePos + */ +static +void +variable_pos_discard(VariablePos *variable_pos) +{ + pfree(variable_pos); +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 79d5e96021..87591a8d43 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,11 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2649,19 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2689,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Sat_Dec_21_18_20_04_2024_526)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v25-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v26 5/9] Row pattern recognition patch (executor). @ 2024-12-30 12:44 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-30 12:44 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1843 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 58 + 4 files changed, 1933 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..8333021623 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,33 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +#define STRSET_FROZEN (1 << 0) /* string is frozen */ +#define STRSET_DISCARDED (1 << 1) /* string is scheduled to be discarded */ +#define STRSET_MATCHED (1 << 2) /* string is confirmed to be matched + * with pattern */ + +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ + int *info; /* an array of information bit per StringInfo. + * see above */ +} StringSet; + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +214,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +226,60 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(WindowAggState *winstate, + StringSet *input_str_set); +static StringSet *generate_patterns(StringSet *input_str_set, + char *pattern, VariablePos *variable_pos, + char tail_pattern_initial); +static int add_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char c, char *pattern, char tail_pattern_initial, + int resultlen); +static int freeze_pattern(StringInfo old, int old_info, + StringSet *new_str_set, + char *pattern, int resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str, int info); +static StringInfo string_set_get(StringSet *string_set, int index, int *flag); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static VariablePos *variable_pos_build(WindowAggState *winstate); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +856,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +872,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +947,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1017,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1038,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1059,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) + != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) + == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1134,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1358,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2330,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2443,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2620,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2721,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2912,49 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + + /* + * Build variable_pos + */ + if (winstate->defineInitial) + winstate->variable_pos = variable_pos_build(winstate); + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2963,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3125,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3487,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3808,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3922,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4007,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4033,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4070,1428 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringSet *str_set; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + int init_size; + + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + + /* + * makeStringInfo creates initial data size to be 1024 bytes, which is + * too large for us because we only need the initial data as the + * number PATTERN variables (+null terminate), which is usually less + * than 10 bytes. So we reallocate the initial data size as small as + * the number of PATTERN variables. + */ + encoded_str = makeStringInfo(); + pfree(encoded_str->data); + init_size = list_length(winstate->patternVariableList) + 1; + encoded_str->data = (char *) palloc0(init_size); + encoded_str->maxlen = init_size; + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str, 0); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(winstate, str_set); + +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * + * Perform pattern matching using "pattern" against input_str_set. pattern is + * a regular expression string derived from PATTERN clause. Note that the + * regular expression string is prefixed by '^' and followed by initials + * represented in a same way as str_set. str_set is a set of StringInfo. Each + * StringInfo has a string comprising initials of pattern variable strings + * being true in a row. The initials are one of [a-z], parallel to the order + * of variable names in DEFINE clause. Suppose DEFINE has variables START, UP + * and DOWN. If PATTERN has START, UP+ and DOWN, then the initials in PATTERN + * will be 'a', 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(WindowAggState *winstate, StringSet *input_str_set) +{ + char *pattern; /* search regexp pattern */ + VariablePos *variable_pos; + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *new_str_set; + int new_str_size; + int len; + int info; + char tail_pattern_initial; + + /* + * Set last initial char to tail_pattern_initial if we can apply "tail + * pattern initial optimization". If the last regexp component in pattern + * is with '+' quatifier, set the initial to tail_pattern_initial. For + * example if pattern = "ab+", tail_pattern_initial will be 'b'. + * Otherwise, tail_pattern_initial is '\0'. + */ + pattern = winstate->pattern_str->data; + if (pattern[strlen(pattern) - 1] == '+') + tail_pattern_initial = pattern[strlen(pattern) - 2]; + else + tail_pattern_initial = '\0'; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + variable_pos = winstate->variable_pos; + new_str_set = generate_patterns(input_str_set, pattern, variable_pos, + tail_pattern_initial); + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + len = 0; + resultlen = 0; + set_size = string_set_get_size(input_str_set); + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index, &info); + if (s == NULL) + continue; /* no data */ + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + if (info & STRSET_DISCARDED) + continue; + + len = do_pattern_match(pattern, s->data, s->len); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * generate_patterns + * + * Generate all possible pattern variable name initials in 'input_str_set' as + * a set of StringInfo and return it. For example, if we have two rows having + * "ab" (row 0) and "ac" (row 1) in 'input str_set', returned StringSet will + * have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + * 'variable_pos' and 'tail_pattern_initial' are used for pruning + * optimization. + */ +static +StringSet * +generate_patterns(StringSet *input_str_set, char *pattern, + VariablePos *variable_pos, char tail_pattern_initial) +{ + StringSet *old_str_set, + *new_str_set; + int index; + int set_size; + int old_set_size; + int info; + int resultlen; + StringInfo str; + int i; + char *p; + + new_str_set = string_set_init(); + set_size = string_set_get_size(input_str_set); + if (set_size == 0) /* if there's no row in input, return empty + * set */ + return new_str_set; + + resultlen = 0; + + /* + * Generate initial new_string_set for input row 0. + */ + str = string_set_get(input_str_set, 0, &info); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new, 0); + p++; /* next pattern variable */ + } + + /* + * Generate new_string_set for each input row. + */ + for (index = 1; index < set_size; index++) + { + /* previous new str set now becomes old str set */ + old_str_set = new_str_set; + new_str_set = string_set_init(); /* create new string set */ + /* pick up input string */ + str = string_set_get(input_str_set, index, &info); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each row in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + char last_old_char; + int old_str_len; + int old_info; + StringInfo old; + + old = string_set_get(old_str_set, i, &old_info); + p = old->data; + old_str_len = old->len; + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Can this old set be discarded? */ + if (old_info & STRSET_DISCARDED) + continue; /* discard the old string */ + + /* Is this old set frozen? */ + else if (old_info & STRSET_FROZEN) + { + /* if shorter match. we can discard it */ + if (old_str_len < resultlen) + continue; /* discard the shorter string */ + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old, old_info); + old_str_set->str_set[i] = NULL; + continue; + } + + /* + * loop over each pattern variable initial char in the input set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable initial + * character position is greater than or equal to the old + * set's last pattern variable initial character position. For + * example, if the old set's last pattern variable initials + * are "ab", then the new pattern variable initial can be "b" + * or "c" but can not be "a", if the initials in PATTERN is + * something like "a b c" or "a b+ c+" etc. This optimization + * is possible when we only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + + /* + * Satisfied the condition. Add new pattern char to + * new_str_set if it looks good. + */ + resultlen = add_pattern(old, old_info, new_str_set, *p, + pattern, tail_pattern_initial, resultlen); + else + + /* + * The old_str did not satisfy the condition and it cannot + * be extended further. "Freeze" it. + */ + resultlen = freeze_pattern(old, old_info, + new_str_set, pattern, resultlen); + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + return new_str_set; +} + +/* + * add_pattern + * + * Make a copy of 'old' (along with 'old_info' flag) and add new pattern char + * 'c' to it. Then add it to 'new_str_set'. 'pattern' and + * 'tail_pattern_initial' is checked to determine whether the copy is worth to + * add to new_str_set or not. The match length (possibly longer than + * 'resultlen') is returned. + */ +static +int +add_pattern(StringInfo old, int old_info, StringSet *new_str_set, char c, + char *pattern, char tail_pattern_initial, int resultlen) +{ + StringInfo new; + int info; + int len; + + /* + * New char in the input row satisfies the condition above. + */ + new = makeStringInfo(); /* copy source string */ + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + + /* add pattern variable char */ + appendStringInfoChar(new, c); + + /* + * Adhoc optimization. If the first letter in the input string is in the + * head and second position and there's no associated quatifier '+', then + * we can dicard the input because there's no chance to expand the string + * further. + * + * For example, pattern "abc" cannot match "aa". + */ + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + destroyStringInfo(new); + return resultlen; + } + + info = old_info; + + /* + * Check if we can apply "tail pattern initial optimization". If the last + * regexp component in pattern has '+' quantifier, the component is set to + * the last pattern initial. For example if pattern is "ab+", + * tail_pattern_initial will become 'b'. Otherwise, tail_pattern_initial + * is '\0'. If the tail pattern initial optimization is possible, we do + * not need to apply regular expression match again. Suppose we have the + * previous string ended with "b" and the it was confirmed the regular + * expression match, then char 'b' can be added to the string without + * applying the regular expression match again. + */ + if (c == tail_pattern_initial) /* tail pattern initial optimization + * possible? */ + { + /* + * Is already confirmed to be matched with pattern? + */ + if ((info & STRSET_MATCHED) == 0) + { + /* not confirmed yet */ + len = do_pattern_match(pattern, new->data, new->len); + if (len > 0) + info = STRSET_MATCHED; /* set already confirmed flag */ + } + else + + /* + * already confirmed. Use the string length as the matching length + */ + len = new->len; + + /* update the longest match length if needed */ + if (len > resultlen) + resultlen = len; + } + + /* add new StringInfo to the string set */ + string_set_add(new_str_set, new, info); + + return resultlen; +} + +/* + * freeze_pattern + * + * "Freeze" 'old' (along with 'old_info' flag) and add it to + * 'new_str_set'. Frozen string is known to not be expaned fruther. The frozen + * string is check if it satisfies 'pattern'. If it does not, "discarded" + * mark is added. The discarded mark is also added if the match length is + * shorter than the current longest match length. The match length (possibly + * longer than 'resultlen') is returned. + */ +static +int +freeze_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char *pattern, int resultlen) +{ + int len; + StringInfo new; + int new_str_size; + int new_index; + + /* + * We are freezing this pattern string. If the pattern string length is + * shorter than the current longest string length, we don't need to keep + * it. + */ + if (old->len < resultlen) + return resultlen; + + if (old_info & STRSET_MATCHED) + /* we don't need to apply pattern match again */ + len = old->len; + else + { + /* apply pattern match */ + len = do_pattern_match(pattern, old->data, old->len); + if (len <= 0) + { + /* no match. we can discard it */ + return resultlen; + } + } + if (len < resultlen) + { + /* shorter match. we can discard it */ + return resultlen; + } + + /* + * Match length is the longest so far + */ + resultlen = len; /* remember the longest match */ + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* set frozen mark */ + string_set_add(new_str_set, new, STRSET_FROZEN); + + /* + * Search new_str_set to find out frozen entries that have shorter match + * length. Mark them as "discard" so that they are discarded in the next + * round. + */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + int info; + + new = string_set_get(new_str_set, new_index, &info); + + /* + * If this is frozen and is not longer than the current longest match + * length, we don't need to keep this. + */ + if (info & STRSET_FROZEN && new->len < resultlen) + { + /* + * mark this set to discard in the next round + */ + info |= STRSET_DISCARDED; + new_str_set->info[new_index] = info; + } + } + return resultlen; +} + +/* + * do_pattern_match + * + * Perform pattern match using 'pattern' against 'encoded_str' whose length is + * 'len' bytes (without null terminate). Returns matching number of rows if + * matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t *regcache = NULL; + static regex_t preg; + static char patbuf[1024]; /* most recent 'pattern' is cached here */ + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + /* + * Compile regexp if cache does not exist or existing cache is not same as + * "pattern". + */ + if (strcmp(patbuf, pattern)) + { + /* + * The compiled re must live in top memory context because patbuf is + * static data. + */ + MemoryContext oldContext = MemoryContextSwitchTo(TopMemoryContext); + + if (regcache != NULL) + pg_regfree(regcache); /* free previous re */ + + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + MemoryContextSwitchTo(oldContext); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + + /* save cache */ + regcache = &preg; + strncpy(patbuf, pattern, sizeof(patbuf)); + } + + data = (pg_wchar *) palloc((len + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +/* + * evaluate_pattern + * + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->info = palloc0(set_size * sizeof(int)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str, int info) +{ + Size set_size; + Size old_set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + old_set_size = set_size; + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->info = repalloc0(string_set->info, + old_set_size * sizeof(int), + set_size * sizeof(int)); + string_set->set_size = set_size; + } + + string_set->info[string_set->set_index] = info; + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index, int *info) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + *info = string_set->info[index]; + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->info); + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_build + * + * Build VariablePos structure and return it. + */ +static +VariablePos * +variable_pos_build(WindowAggState *winstate) +{ + VariablePos *variable_pos; + StringInfo pattern_str; + int initial_index = 0; + ListCell *lc1, + *lc2; + + variable_pos = winstate->variable_pos = variable_pos_init(); + pattern_str = winstate->pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + return variable_pos; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1590b64392..f96782fd6a 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,37 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + +/* + * Allowed PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postions in PATTERN */ +} VariablePos; + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2675,21 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + VariablePos *variable_pos; /* list of pattern variable positions */ + StringInfo pattern_str; /* PATTERN initials */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2717,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Dec_30_22_37_18_2024_171)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v26-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v26 5/9] Row pattern recognition patch (executor). @ 2024-12-30 12:44 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-30 12:44 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1843 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 58 + 4 files changed, 1933 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..8333021623 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,33 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +#define STRSET_FROZEN (1 << 0) /* string is frozen */ +#define STRSET_DISCARDED (1 << 1) /* string is scheduled to be discarded */ +#define STRSET_MATCHED (1 << 2) /* string is confirmed to be matched + * with pattern */ + +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ + int *info; /* an array of information bit per StringInfo. + * see above */ +} StringSet; + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +214,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +226,60 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(WindowAggState *winstate, + StringSet *input_str_set); +static StringSet *generate_patterns(StringSet *input_str_set, + char *pattern, VariablePos *variable_pos, + char tail_pattern_initial); +static int add_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char c, char *pattern, char tail_pattern_initial, + int resultlen); +static int freeze_pattern(StringInfo old, int old_info, + StringSet *new_str_set, + char *pattern, int resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str, int info); +static StringInfo string_set_get(StringSet *string_set, int index, int *flag); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static VariablePos *variable_pos_build(WindowAggState *winstate); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +856,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +872,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +947,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1017,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1038,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1059,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) + != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) + == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1134,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1358,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2330,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2443,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2620,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2721,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2912,49 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + + /* + * Build variable_pos + */ + if (winstate->defineInitial) + winstate->variable_pos = variable_pos_build(winstate); + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2963,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3125,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3487,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3808,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3922,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4007,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4033,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4070,1428 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringSet *str_set; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + int init_size; + + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + + /* + * makeStringInfo creates initial data size to be 1024 bytes, which is + * too large for us because we only need the initial data as the + * number PATTERN variables (+null terminate), which is usually less + * than 10 bytes. So we reallocate the initial data size as small as + * the number of PATTERN variables. + */ + encoded_str = makeStringInfo(); + pfree(encoded_str->data); + init_size = list_length(winstate->patternVariableList) + 1; + encoded_str->data = (char *) palloc0(init_size); + encoded_str->maxlen = init_size; + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str, 0); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(winstate, str_set); + +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * + * Perform pattern matching using "pattern" against input_str_set. pattern is + * a regular expression string derived from PATTERN clause. Note that the + * regular expression string is prefixed by '^' and followed by initials + * represented in a same way as str_set. str_set is a set of StringInfo. Each + * StringInfo has a string comprising initials of pattern variable strings + * being true in a row. The initials are one of [a-z], parallel to the order + * of variable names in DEFINE clause. Suppose DEFINE has variables START, UP + * and DOWN. If PATTERN has START, UP+ and DOWN, then the initials in PATTERN + * will be 'a', 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(WindowAggState *winstate, StringSet *input_str_set) +{ + char *pattern; /* search regexp pattern */ + VariablePos *variable_pos; + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *new_str_set; + int new_str_size; + int len; + int info; + char tail_pattern_initial; + + /* + * Set last initial char to tail_pattern_initial if we can apply "tail + * pattern initial optimization". If the last regexp component in pattern + * is with '+' quatifier, set the initial to tail_pattern_initial. For + * example if pattern = "ab+", tail_pattern_initial will be 'b'. + * Otherwise, tail_pattern_initial is '\0'. + */ + pattern = winstate->pattern_str->data; + if (pattern[strlen(pattern) - 1] == '+') + tail_pattern_initial = pattern[strlen(pattern) - 2]; + else + tail_pattern_initial = '\0'; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + variable_pos = winstate->variable_pos; + new_str_set = generate_patterns(input_str_set, pattern, variable_pos, + tail_pattern_initial); + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + len = 0; + resultlen = 0; + set_size = string_set_get_size(input_str_set); + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index, &info); + if (s == NULL) + continue; /* no data */ + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + if (info & STRSET_DISCARDED) + continue; + + len = do_pattern_match(pattern, s->data, s->len); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * generate_patterns + * + * Generate all possible pattern variable name initials in 'input_str_set' as + * a set of StringInfo and return it. For example, if we have two rows having + * "ab" (row 0) and "ac" (row 1) in 'input str_set', returned StringSet will + * have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + * 'variable_pos' and 'tail_pattern_initial' are used for pruning + * optimization. + */ +static +StringSet * +generate_patterns(StringSet *input_str_set, char *pattern, + VariablePos *variable_pos, char tail_pattern_initial) +{ + StringSet *old_str_set, + *new_str_set; + int index; + int set_size; + int old_set_size; + int info; + int resultlen; + StringInfo str; + int i; + char *p; + + new_str_set = string_set_init(); + set_size = string_set_get_size(input_str_set); + if (set_size == 0) /* if there's no row in input, return empty + * set */ + return new_str_set; + + resultlen = 0; + + /* + * Generate initial new_string_set for input row 0. + */ + str = string_set_get(input_str_set, 0, &info); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new, 0); + p++; /* next pattern variable */ + } + + /* + * Generate new_string_set for each input row. + */ + for (index = 1; index < set_size; index++) + { + /* previous new str set now becomes old str set */ + old_str_set = new_str_set; + new_str_set = string_set_init(); /* create new string set */ + /* pick up input string */ + str = string_set_get(input_str_set, index, &info); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each row in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + char last_old_char; + int old_str_len; + int old_info; + StringInfo old; + + old = string_set_get(old_str_set, i, &old_info); + p = old->data; + old_str_len = old->len; + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Can this old set be discarded? */ + if (old_info & STRSET_DISCARDED) + continue; /* discard the old string */ + + /* Is this old set frozen? */ + else if (old_info & STRSET_FROZEN) + { + /* if shorter match. we can discard it */ + if (old_str_len < resultlen) + continue; /* discard the shorter string */ + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old, old_info); + old_str_set->str_set[i] = NULL; + continue; + } + + /* + * loop over each pattern variable initial char in the input set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable initial + * character position is greater than or equal to the old + * set's last pattern variable initial character position. For + * example, if the old set's last pattern variable initials + * are "ab", then the new pattern variable initial can be "b" + * or "c" but can not be "a", if the initials in PATTERN is + * something like "a b c" or "a b+ c+" etc. This optimization + * is possible when we only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + + /* + * Satisfied the condition. Add new pattern char to + * new_str_set if it looks good. + */ + resultlen = add_pattern(old, old_info, new_str_set, *p, + pattern, tail_pattern_initial, resultlen); + else + + /* + * The old_str did not satisfy the condition and it cannot + * be extended further. "Freeze" it. + */ + resultlen = freeze_pattern(old, old_info, + new_str_set, pattern, resultlen); + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + return new_str_set; +} + +/* + * add_pattern + * + * Make a copy of 'old' (along with 'old_info' flag) and add new pattern char + * 'c' to it. Then add it to 'new_str_set'. 'pattern' and + * 'tail_pattern_initial' is checked to determine whether the copy is worth to + * add to new_str_set or not. The match length (possibly longer than + * 'resultlen') is returned. + */ +static +int +add_pattern(StringInfo old, int old_info, StringSet *new_str_set, char c, + char *pattern, char tail_pattern_initial, int resultlen) +{ + StringInfo new; + int info; + int len; + + /* + * New char in the input row satisfies the condition above. + */ + new = makeStringInfo(); /* copy source string */ + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + + /* add pattern variable char */ + appendStringInfoChar(new, c); + + /* + * Adhoc optimization. If the first letter in the input string is in the + * head and second position and there's no associated quatifier '+', then + * we can dicard the input because there's no chance to expand the string + * further. + * + * For example, pattern "abc" cannot match "aa". + */ + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + destroyStringInfo(new); + return resultlen; + } + + info = old_info; + + /* + * Check if we can apply "tail pattern initial optimization". If the last + * regexp component in pattern has '+' quantifier, the component is set to + * the last pattern initial. For example if pattern is "ab+", + * tail_pattern_initial will become 'b'. Otherwise, tail_pattern_initial + * is '\0'. If the tail pattern initial optimization is possible, we do + * not need to apply regular expression match again. Suppose we have the + * previous string ended with "b" and the it was confirmed the regular + * expression match, then char 'b' can be added to the string without + * applying the regular expression match again. + */ + if (c == tail_pattern_initial) /* tail pattern initial optimization + * possible? */ + { + /* + * Is already confirmed to be matched with pattern? + */ + if ((info & STRSET_MATCHED) == 0) + { + /* not confirmed yet */ + len = do_pattern_match(pattern, new->data, new->len); + if (len > 0) + info = STRSET_MATCHED; /* set already confirmed flag */ + } + else + + /* + * already confirmed. Use the string length as the matching length + */ + len = new->len; + + /* update the longest match length if needed */ + if (len > resultlen) + resultlen = len; + } + + /* add new StringInfo to the string set */ + string_set_add(new_str_set, new, info); + + return resultlen; +} + +/* + * freeze_pattern + * + * "Freeze" 'old' (along with 'old_info' flag) and add it to + * 'new_str_set'. Frozen string is known to not be expaned fruther. The frozen + * string is check if it satisfies 'pattern'. If it does not, "discarded" + * mark is added. The discarded mark is also added if the match length is + * shorter than the current longest match length. The match length (possibly + * longer than 'resultlen') is returned. + */ +static +int +freeze_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char *pattern, int resultlen) +{ + int len; + StringInfo new; + int new_str_size; + int new_index; + + /* + * We are freezing this pattern string. If the pattern string length is + * shorter than the current longest string length, we don't need to keep + * it. + */ + if (old->len < resultlen) + return resultlen; + + if (old_info & STRSET_MATCHED) + /* we don't need to apply pattern match again */ + len = old->len; + else + { + /* apply pattern match */ + len = do_pattern_match(pattern, old->data, old->len); + if (len <= 0) + { + /* no match. we can discard it */ + return resultlen; + } + } + if (len < resultlen) + { + /* shorter match. we can discard it */ + return resultlen; + } + + /* + * Match length is the longest so far + */ + resultlen = len; /* remember the longest match */ + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* set frozen mark */ + string_set_add(new_str_set, new, STRSET_FROZEN); + + /* + * Search new_str_set to find out frozen entries that have shorter match + * length. Mark them as "discard" so that they are discarded in the next + * round. + */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + int info; + + new = string_set_get(new_str_set, new_index, &info); + + /* + * If this is frozen and is not longer than the current longest match + * length, we don't need to keep this. + */ + if (info & STRSET_FROZEN && new->len < resultlen) + { + /* + * mark this set to discard in the next round + */ + info |= STRSET_DISCARDED; + new_str_set->info[new_index] = info; + } + } + return resultlen; +} + +/* + * do_pattern_match + * + * Perform pattern match using 'pattern' against 'encoded_str' whose length is + * 'len' bytes (without null terminate). Returns matching number of rows if + * matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t *regcache = NULL; + static regex_t preg; + static char patbuf[1024]; /* most recent 'pattern' is cached here */ + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + /* + * Compile regexp if cache does not exist or existing cache is not same as + * "pattern". + */ + if (strcmp(patbuf, pattern)) + { + /* + * The compiled re must live in top memory context because patbuf is + * static data. + */ + MemoryContext oldContext = MemoryContextSwitchTo(TopMemoryContext); + + if (regcache != NULL) + pg_regfree(regcache); /* free previous re */ + + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + MemoryContextSwitchTo(oldContext); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + + /* save cache */ + regcache = &preg; + strncpy(patbuf, pattern, sizeof(patbuf)); + } + + data = (pg_wchar *) palloc((len + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +/* + * evaluate_pattern + * + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->info = palloc0(set_size * sizeof(int)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str, int info) +{ + Size set_size; + Size old_set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + old_set_size = set_size; + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->info = repalloc0(string_set->info, + old_set_size * sizeof(int), + set_size * sizeof(int)); + string_set->set_size = set_size; + } + + string_set->info[string_set->set_index] = info; + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index, int *info) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + *info = string_set->info[index]; + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->info); + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_build + * + * Build VariablePos structure and return it. + */ +static +VariablePos * +variable_pos_build(WindowAggState *winstate) +{ + VariablePos *variable_pos; + StringInfo pattern_str; + int initial_index = 0; + ListCell *lc1, + *lc2; + + variable_pos = winstate->variable_pos = variable_pos_init(); + pattern_str = winstate->pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + return variable_pos; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1590b64392..f96782fd6a 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,37 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + +/* + * Allowed PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postions in PATTERN */ +} VariablePos; + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2675,21 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + VariablePos *variable_pos; /* list of pattern variable positions */ + StringInfo pattern_str; /* PATTERN initials */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2717,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Dec_30_22_37_18_2024_171)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v26-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v26 5/9] Row pattern recognition patch (executor). @ 2024-12-30 12:44 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-30 12:44 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1843 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 58 + 4 files changed, 1933 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..8333021623 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,33 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +#define STRSET_FROZEN (1 << 0) /* string is frozen */ +#define STRSET_DISCARDED (1 << 1) /* string is scheduled to be discarded */ +#define STRSET_MATCHED (1 << 2) /* string is confirmed to be matched + * with pattern */ + +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ + int *info; /* an array of information bit per StringInfo. + * see above */ +} StringSet; + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +214,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +226,60 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(WindowAggState *winstate, + StringSet *input_str_set); +static StringSet *generate_patterns(StringSet *input_str_set, + char *pattern, VariablePos *variable_pos, + char tail_pattern_initial); +static int add_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char c, char *pattern, char tail_pattern_initial, + int resultlen); +static int freeze_pattern(StringInfo old, int old_info, + StringSet *new_str_set, + char *pattern, int resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str, int info); +static StringInfo string_set_get(StringSet *string_set, int index, int *flag); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static VariablePos *variable_pos_build(WindowAggState *winstate); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +856,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +872,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +947,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1017,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1038,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1059,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) + != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) + == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1134,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1358,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2330,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2443,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2620,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2721,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2912,49 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + + /* + * Build variable_pos + */ + if (winstate->defineInitial) + winstate->variable_pos = variable_pos_build(winstate); + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2963,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3125,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3487,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3808,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3922,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4007,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4033,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4070,1428 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringSet *str_set; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + int init_size; + + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + + /* + * makeStringInfo creates initial data size to be 1024 bytes, which is + * too large for us because we only need the initial data as the + * number PATTERN variables (+null terminate), which is usually less + * than 10 bytes. So we reallocate the initial data size as small as + * the number of PATTERN variables. + */ + encoded_str = makeStringInfo(); + pfree(encoded_str->data); + init_size = list_length(winstate->patternVariableList) + 1; + encoded_str->data = (char *) palloc0(init_size); + encoded_str->maxlen = init_size; + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str, 0); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(winstate, str_set); + +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * + * Perform pattern matching using "pattern" against input_str_set. pattern is + * a regular expression string derived from PATTERN clause. Note that the + * regular expression string is prefixed by '^' and followed by initials + * represented in a same way as str_set. str_set is a set of StringInfo. Each + * StringInfo has a string comprising initials of pattern variable strings + * being true in a row. The initials are one of [a-z], parallel to the order + * of variable names in DEFINE clause. Suppose DEFINE has variables START, UP + * and DOWN. If PATTERN has START, UP+ and DOWN, then the initials in PATTERN + * will be 'a', 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(WindowAggState *winstate, StringSet *input_str_set) +{ + char *pattern; /* search regexp pattern */ + VariablePos *variable_pos; + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *new_str_set; + int new_str_size; + int len; + int info; + char tail_pattern_initial; + + /* + * Set last initial char to tail_pattern_initial if we can apply "tail + * pattern initial optimization". If the last regexp component in pattern + * is with '+' quatifier, set the initial to tail_pattern_initial. For + * example if pattern = "ab+", tail_pattern_initial will be 'b'. + * Otherwise, tail_pattern_initial is '\0'. + */ + pattern = winstate->pattern_str->data; + if (pattern[strlen(pattern) - 1] == '+') + tail_pattern_initial = pattern[strlen(pattern) - 2]; + else + tail_pattern_initial = '\0'; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + variable_pos = winstate->variable_pos; + new_str_set = generate_patterns(input_str_set, pattern, variable_pos, + tail_pattern_initial); + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + len = 0; + resultlen = 0; + set_size = string_set_get_size(input_str_set); + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index, &info); + if (s == NULL) + continue; /* no data */ + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + if (info & STRSET_DISCARDED) + continue; + + len = do_pattern_match(pattern, s->data, s->len); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * generate_patterns + * + * Generate all possible pattern variable name initials in 'input_str_set' as + * a set of StringInfo and return it. For example, if we have two rows having + * "ab" (row 0) and "ac" (row 1) in 'input str_set', returned StringSet will + * have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + * 'variable_pos' and 'tail_pattern_initial' are used for pruning + * optimization. + */ +static +StringSet * +generate_patterns(StringSet *input_str_set, char *pattern, + VariablePos *variable_pos, char tail_pattern_initial) +{ + StringSet *old_str_set, + *new_str_set; + int index; + int set_size; + int old_set_size; + int info; + int resultlen; + StringInfo str; + int i; + char *p; + + new_str_set = string_set_init(); + set_size = string_set_get_size(input_str_set); + if (set_size == 0) /* if there's no row in input, return empty + * set */ + return new_str_set; + + resultlen = 0; + + /* + * Generate initial new_string_set for input row 0. + */ + str = string_set_get(input_str_set, 0, &info); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new, 0); + p++; /* next pattern variable */ + } + + /* + * Generate new_string_set for each input row. + */ + for (index = 1; index < set_size; index++) + { + /* previous new str set now becomes old str set */ + old_str_set = new_str_set; + new_str_set = string_set_init(); /* create new string set */ + /* pick up input string */ + str = string_set_get(input_str_set, index, &info); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each row in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + char last_old_char; + int old_str_len; + int old_info; + StringInfo old; + + old = string_set_get(old_str_set, i, &old_info); + p = old->data; + old_str_len = old->len; + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Can this old set be discarded? */ + if (old_info & STRSET_DISCARDED) + continue; /* discard the old string */ + + /* Is this old set frozen? */ + else if (old_info & STRSET_FROZEN) + { + /* if shorter match. we can discard it */ + if (old_str_len < resultlen) + continue; /* discard the shorter string */ + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old, old_info); + old_str_set->str_set[i] = NULL; + continue; + } + + /* + * loop over each pattern variable initial char in the input set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable initial + * character position is greater than or equal to the old + * set's last pattern variable initial character position. For + * example, if the old set's last pattern variable initials + * are "ab", then the new pattern variable initial can be "b" + * or "c" but can not be "a", if the initials in PATTERN is + * something like "a b c" or "a b+ c+" etc. This optimization + * is possible when we only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + + /* + * Satisfied the condition. Add new pattern char to + * new_str_set if it looks good. + */ + resultlen = add_pattern(old, old_info, new_str_set, *p, + pattern, tail_pattern_initial, resultlen); + else + + /* + * The old_str did not satisfy the condition and it cannot + * be extended further. "Freeze" it. + */ + resultlen = freeze_pattern(old, old_info, + new_str_set, pattern, resultlen); + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + return new_str_set; +} + +/* + * add_pattern + * + * Make a copy of 'old' (along with 'old_info' flag) and add new pattern char + * 'c' to it. Then add it to 'new_str_set'. 'pattern' and + * 'tail_pattern_initial' is checked to determine whether the copy is worth to + * add to new_str_set or not. The match length (possibly longer than + * 'resultlen') is returned. + */ +static +int +add_pattern(StringInfo old, int old_info, StringSet *new_str_set, char c, + char *pattern, char tail_pattern_initial, int resultlen) +{ + StringInfo new; + int info; + int len; + + /* + * New char in the input row satisfies the condition above. + */ + new = makeStringInfo(); /* copy source string */ + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + + /* add pattern variable char */ + appendStringInfoChar(new, c); + + /* + * Adhoc optimization. If the first letter in the input string is in the + * head and second position and there's no associated quatifier '+', then + * we can dicard the input because there's no chance to expand the string + * further. + * + * For example, pattern "abc" cannot match "aa". + */ + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + destroyStringInfo(new); + return resultlen; + } + + info = old_info; + + /* + * Check if we can apply "tail pattern initial optimization". If the last + * regexp component in pattern has '+' quantifier, the component is set to + * the last pattern initial. For example if pattern is "ab+", + * tail_pattern_initial will become 'b'. Otherwise, tail_pattern_initial + * is '\0'. If the tail pattern initial optimization is possible, we do + * not need to apply regular expression match again. Suppose we have the + * previous string ended with "b" and the it was confirmed the regular + * expression match, then char 'b' can be added to the string without + * applying the regular expression match again. + */ + if (c == tail_pattern_initial) /* tail pattern initial optimization + * possible? */ + { + /* + * Is already confirmed to be matched with pattern? + */ + if ((info & STRSET_MATCHED) == 0) + { + /* not confirmed yet */ + len = do_pattern_match(pattern, new->data, new->len); + if (len > 0) + info = STRSET_MATCHED; /* set already confirmed flag */ + } + else + + /* + * already confirmed. Use the string length as the matching length + */ + len = new->len; + + /* update the longest match length if needed */ + if (len > resultlen) + resultlen = len; + } + + /* add new StringInfo to the string set */ + string_set_add(new_str_set, new, info); + + return resultlen; +} + +/* + * freeze_pattern + * + * "Freeze" 'old' (along with 'old_info' flag) and add it to + * 'new_str_set'. Frozen string is known to not be expaned fruther. The frozen + * string is check if it satisfies 'pattern'. If it does not, "discarded" + * mark is added. The discarded mark is also added if the match length is + * shorter than the current longest match length. The match length (possibly + * longer than 'resultlen') is returned. + */ +static +int +freeze_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char *pattern, int resultlen) +{ + int len; + StringInfo new; + int new_str_size; + int new_index; + + /* + * We are freezing this pattern string. If the pattern string length is + * shorter than the current longest string length, we don't need to keep + * it. + */ + if (old->len < resultlen) + return resultlen; + + if (old_info & STRSET_MATCHED) + /* we don't need to apply pattern match again */ + len = old->len; + else + { + /* apply pattern match */ + len = do_pattern_match(pattern, old->data, old->len); + if (len <= 0) + { + /* no match. we can discard it */ + return resultlen; + } + } + if (len < resultlen) + { + /* shorter match. we can discard it */ + return resultlen; + } + + /* + * Match length is the longest so far + */ + resultlen = len; /* remember the longest match */ + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* set frozen mark */ + string_set_add(new_str_set, new, STRSET_FROZEN); + + /* + * Search new_str_set to find out frozen entries that have shorter match + * length. Mark them as "discard" so that they are discarded in the next + * round. + */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + int info; + + new = string_set_get(new_str_set, new_index, &info); + + /* + * If this is frozen and is not longer than the current longest match + * length, we don't need to keep this. + */ + if (info & STRSET_FROZEN && new->len < resultlen) + { + /* + * mark this set to discard in the next round + */ + info |= STRSET_DISCARDED; + new_str_set->info[new_index] = info; + } + } + return resultlen; +} + +/* + * do_pattern_match + * + * Perform pattern match using 'pattern' against 'encoded_str' whose length is + * 'len' bytes (without null terminate). Returns matching number of rows if + * matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t *regcache = NULL; + static regex_t preg; + static char patbuf[1024]; /* most recent 'pattern' is cached here */ + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + /* + * Compile regexp if cache does not exist or existing cache is not same as + * "pattern". + */ + if (strcmp(patbuf, pattern)) + { + /* + * The compiled re must live in top memory context because patbuf is + * static data. + */ + MemoryContext oldContext = MemoryContextSwitchTo(TopMemoryContext); + + if (regcache != NULL) + pg_regfree(regcache); /* free previous re */ + + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + MemoryContextSwitchTo(oldContext); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + + /* save cache */ + regcache = &preg; + strncpy(patbuf, pattern, sizeof(patbuf)); + } + + data = (pg_wchar *) palloc((len + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +/* + * evaluate_pattern + * + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->info = palloc0(set_size * sizeof(int)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str, int info) +{ + Size set_size; + Size old_set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + old_set_size = set_size; + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->info = repalloc0(string_set->info, + old_set_size * sizeof(int), + set_size * sizeof(int)); + string_set->set_size = set_size; + } + + string_set->info[string_set->set_index] = info; + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index, int *info) +{ + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + *info = string_set->info[index]; + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->info); + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_build + * + * Build VariablePos structure and return it. + */ +static +VariablePos * +variable_pos_build(WindowAggState *winstate) +{ + VariablePos *variable_pos; + StringInfo pattern_str; + int initial_index = 0; + ListCell *lc1, + *lc2; + + variable_pos = winstate->variable_pos = variable_pos_init(); + pattern_str = winstate->pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + return variable_pos; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1590b64392..f96782fd6a 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,37 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + +/* + * Allowed PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postions in PATTERN */ +} VariablePos; + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2675,21 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + VariablePos *variable_pos; /* list of pattern variable positions */ + StringInfo pattern_str; /* PATTERN initials */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2717,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Mon_Dec_30_22_37_18_2024_171)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v26-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v27 5/9] Row pattern recognition patch (executor). @ 2024-12-30 23:53 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-30 23:53 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1845 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 58 + 4 files changed, 1935 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..2a06676572 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,33 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +#define STRSET_FROZEN (1 << 0) /* string is frozen */ +#define STRSET_DISCARDED (1 << 1) /* string is scheduled to be discarded */ +#define STRSET_MATCHED (1 << 2) /* string is confirmed to be matched + * with pattern */ + +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ + int *info; /* an array of information bit per StringInfo. + * see above */ +} StringSet; + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +214,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +226,60 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(WindowAggState *winstate, + StringSet *input_str_set); +static StringSet *generate_patterns(StringSet *input_str_set, + char *pattern, VariablePos *variable_pos, + char tail_pattern_initial); +static int add_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char c, char *pattern, char tail_pattern_initial, + int resultlen); +static int freeze_pattern(StringInfo old, int old_info, + StringSet *new_str_set, + char *pattern, int resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str, int info); +static StringInfo string_set_get(StringSet *string_set, int index, int *flag); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static VariablePos *variable_pos_build(WindowAggState *winstate); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +856,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +872,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +947,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1017,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1038,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1059,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) + != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) + == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1134,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1358,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2330,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2443,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2620,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2721,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2912,49 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + + /* + * Build variable_pos + */ + if (winstate->defineInitial) + winstate->variable_pos = variable_pos_build(winstate); + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2963,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3125,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3487,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3808,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3922,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4007,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4033,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4070,1430 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringSet *str_set; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + int init_size; + + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + + /* + * makeStringInfo creates initial data size to be 1024 bytes, which is + * too large for us because we only need the initial data as the + * number PATTERN variables (+null terminate), which is usually less + * than 10 bytes. So we reallocate the initial data size as small as + * the number of PATTERN variables. + */ + encoded_str = makeStringInfo(); + pfree(encoded_str->data); + init_size = list_length(winstate->patternVariableList) + 1; + encoded_str->data = (char *) palloc0(init_size); + encoded_str->maxlen = init_size; + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str, 0); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(winstate, str_set); + +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * + * Perform pattern matching using "pattern" against input_str_set. pattern is + * a regular expression string derived from PATTERN clause. Note that the + * regular expression string is prefixed by '^' and followed by initials + * represented in a same way as str_set. str_set is a set of StringInfo. Each + * StringInfo has a string comprising initials of pattern variable strings + * being true in a row. The initials are one of [a-z], parallel to the order + * of variable names in DEFINE clause. Suppose DEFINE has variables START, UP + * and DOWN. If PATTERN has START, UP+ and DOWN, then the initials in PATTERN + * will be 'a', 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(WindowAggState *winstate, StringSet *input_str_set) +{ + char *pattern; /* search regexp pattern */ + VariablePos *variable_pos; + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *new_str_set; + int new_str_size; + int len; + int info; + char tail_pattern_initial; + + /* + * Set last initial char to tail_pattern_initial if we can apply "tail + * pattern initial optimization". If the last regexp component in pattern + * is with '+' quatifier, set the initial to tail_pattern_initial. For + * example if pattern = "ab+", tail_pattern_initial will be 'b'. + * Otherwise, tail_pattern_initial is '\0'. + */ + pattern = winstate->pattern_str->data; + if (pattern[strlen(pattern) - 1] == '+') + tail_pattern_initial = pattern[strlen(pattern) - 2]; + else + tail_pattern_initial = '\0'; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + variable_pos = winstate->variable_pos; + new_str_set = generate_patterns(input_str_set, pattern, variable_pos, + tail_pattern_initial); + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + len = 0; + resultlen = 0; + set_size = string_set_get_size(input_str_set); + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index, &info); + if (s == NULL) + continue; /* no data */ + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + if (info & STRSET_DISCARDED) + continue; + + len = do_pattern_match(pattern, s->data, s->len); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * generate_patterns + * + * Generate all possible pattern variable name initials in 'input_str_set' as + * a set of StringInfo and return it. For example, if we have two rows having + * "ab" (row 0) and "ac" (row 1) in 'input str_set', returned StringSet will + * have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + * 'variable_pos' and 'tail_pattern_initial' are used for pruning + * optimization. + */ +static +StringSet * +generate_patterns(StringSet *input_str_set, char *pattern, + VariablePos *variable_pos, char tail_pattern_initial) +{ + StringSet *old_str_set, + *new_str_set; + int index; + int set_size; + int old_set_size; + int info; + int resultlen; + StringInfo str; + int i; + char *p; + + new_str_set = string_set_init(); + set_size = string_set_get_size(input_str_set); + if (set_size == 0) /* if there's no row in input, return empty + * set */ + return new_str_set; + + resultlen = 0; + + /* + * Generate initial new_string_set for input row 0. + */ + str = string_set_get(input_str_set, 0, &info); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new, 0); + p++; /* next pattern variable */ + } + + /* + * Generate new_string_set for each input row. + */ + for (index = 1; index < set_size; index++) + { + /* previous new str set now becomes old str set */ + old_str_set = new_str_set; + new_str_set = string_set_init(); /* create new string set */ + /* pick up input string */ + str = string_set_get(input_str_set, index, &info); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each row in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + char last_old_char; + int old_str_len; + int old_info; + StringInfo old; + + old = string_set_get(old_str_set, i, &old_info); + p = old->data; + old_str_len = old->len; + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Can this old set be discarded? */ + if (old_info & STRSET_DISCARDED) + continue; /* discard the old string */ + + /* Is this old set frozen? */ + else if (old_info & STRSET_FROZEN) + { + /* if shorter match. we can discard it */ + if (old_str_len < resultlen) + continue; /* discard the shorter string */ + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old, old_info); + old_str_set->str_set[i] = NULL; + continue; + } + + /* + * loop over each pattern variable initial char in the input set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable initial + * character position is greater than or equal to the old + * set's last pattern variable initial character position. For + * example, if the old set's last pattern variable initials + * are "ab", then the new pattern variable initial can be "b" + * or "c" but can not be "a", if the initials in PATTERN is + * something like "a b c" or "a b+ c+" etc. This optimization + * is possible when we only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + + /* + * Satisfied the condition. Add new pattern char to + * new_str_set if it looks good. + */ + resultlen = add_pattern(old, old_info, new_str_set, *p, + pattern, tail_pattern_initial, resultlen); + else + + /* + * The old_str did not satisfy the condition and it cannot + * be extended further. "Freeze" it. + */ + resultlen = freeze_pattern(old, old_info, + new_str_set, pattern, resultlen); + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + return new_str_set; +} + +/* + * add_pattern + * + * Make a copy of 'old' (along with 'old_info' flag) and add new pattern char + * 'c' to it. Then add it to 'new_str_set'. 'pattern' and + * 'tail_pattern_initial' is checked to determine whether the copy is worth to + * add to new_str_set or not. The match length (possibly longer than + * 'resultlen') is returned. + */ +static +int +add_pattern(StringInfo old, int old_info, StringSet *new_str_set, char c, + char *pattern, char tail_pattern_initial, int resultlen) +{ + StringInfo new; + int info; + int len; + + /* + * New char in the input row satisfies the condition above. + */ + new = makeStringInfo(); /* copy source string */ + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + + /* add pattern variable char */ + appendStringInfoChar(new, c); + + /* + * Adhoc optimization. If the first letter in the input string is in the + * head and second position and there's no associated quatifier '+', then + * we can dicard the input because there's no chance to expand the string + * further. + * + * For example, pattern "abc" cannot match "aa". + */ + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + destroyStringInfo(new); + return resultlen; + } + + info = old_info; + + /* + * Check if we can apply "tail pattern initial optimization". If the last + * regexp component in pattern has '+' quantifier, the component is set to + * the last pattern initial. For example if pattern is "ab+", + * tail_pattern_initial will become 'b'. Otherwise, tail_pattern_initial + * is '\0'. If the tail pattern initial optimization is possible, we do + * not need to apply regular expression match again. Suppose we have the + * previous string ended with "b" and the it was confirmed the regular + * expression match, then char 'b' can be added to the string without + * applying the regular expression match again. + */ + if (c == tail_pattern_initial) /* tail pattern initial optimization + * possible? */ + { + /* + * Is already confirmed to be matched with pattern? + */ + if ((info & STRSET_MATCHED) == 0) + { + /* not confirmed yet */ + len = do_pattern_match(pattern, new->data, new->len); + if (len > 0) + info = STRSET_MATCHED; /* set already confirmed flag */ + } + else + + /* + * already confirmed. Use the string length as the matching length + */ + len = new->len; + + /* update the longest match length if needed */ + if (len > resultlen) + resultlen = len; + } + + /* add new StringInfo to the string set */ + string_set_add(new_str_set, new, info); + + return resultlen; +} + +/* + * freeze_pattern + * + * "Freeze" 'old' (along with 'old_info' flag) and add it to + * 'new_str_set'. Frozen string is known to not be expanded further. The frozen + * string is check if it satisfies 'pattern'. If it does not, "discarded" + * mark is added. The discarded mark is also added if the match length is + * shorter than the current longest match length. The match length (possibly + * longer than 'resultlen') is returned. + */ +static +int +freeze_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char *pattern, int resultlen) +{ + int len; + StringInfo new; + int new_str_size; + int new_index; + + /* + * We are freezing this pattern string. If the pattern string length is + * shorter than the current longest string length, we don't need to keep + * it. + */ + if (old->len < resultlen) + return resultlen; + + if (old_info & STRSET_MATCHED) + /* we don't need to apply pattern match again */ + len = old->len; + else + { + /* apply pattern match */ + len = do_pattern_match(pattern, old->data, old->len); + if (len <= 0) + { + /* no match. we can discard it */ + return resultlen; + } + } + if (len < resultlen) + { + /* shorter match. we can discard it */ + return resultlen; + } + + /* + * Match length is the longest so far + */ + resultlen = len; /* remember the longest match */ + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* set frozen mark */ + string_set_add(new_str_set, new, STRSET_FROZEN); + + /* + * Search new_str_set to find out frozen entries that have shorter match + * length. Mark them as "discard" so that they are discarded in the next + * round. + */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + int info; + + new = string_set_get(new_str_set, new_index, &info); + + /* + * If this is frozen and is not longer than the current longest match + * length, we don't need to keep this. + */ + if (info & STRSET_FROZEN && new->len < resultlen) + { + /* + * mark this set to discard in the next round + */ + info |= STRSET_DISCARDED; + new_str_set->info[new_index] = info; + } + } + return resultlen; +} + +/* + * do_pattern_match + * + * Perform pattern match using 'pattern' against 'encoded_str' whose length is + * 'len' bytes (without null terminate). Returns matching number of rows if + * matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t *regcache = NULL; + static regex_t preg; + static char patbuf[1024]; /* most recent 'pattern' is cached here */ + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + /* + * Compile regexp if cache does not exist or existing cache is not same as + * "pattern". + */ + if (strcmp(patbuf, pattern)) + { + /* + * The compiled re must live in top memory context because patbuf is + * static data. + */ + MemoryContext oldContext = MemoryContextSwitchTo(TopMemoryContext); + + if (regcache != NULL) + pg_regfree(regcache); /* free previous re */ + + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + MemoryContextSwitchTo(oldContext); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + + /* save cache */ + regcache = &preg; + strncpy(patbuf, pattern, sizeof(patbuf)); + } + + data = (pg_wchar *) palloc((len + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +/* + * evaluate_pattern + * + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->info = palloc0(set_size * sizeof(int)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str, int info) +{ + Size set_size; + Size old_set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + old_set_size = set_size; + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->info = repalloc0(string_set->info, + old_set_size * sizeof(int), + set_size * sizeof(int)); + string_set->set_size = set_size; + } + + string_set->info[string_set->set_index] = info; + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index, int *info) +{ + *info = 0; + + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + *info = string_set->info[index]; + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->info); + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_build + * + * Build VariablePos structure and return it. + */ +static +VariablePos * +variable_pos_build(WindowAggState *winstate) +{ + VariablePos *variable_pos; + StringInfo pattern_str; + int initial_index = 0; + ListCell *lc1, + *lc2; + + variable_pos = winstate->variable_pos = variable_pos_init(); + pattern_str = winstate->pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + return variable_pos; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1590b64392..f96782fd6a 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,37 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + +/* + * Allowed PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postions in PATTERN */ +} VariablePos; + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2675,21 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + VariablePos *variable_pos; /* list of pattern variable positions */ + StringInfo pattern_str; /* PATTERN initials */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2717,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Dec_31_08_57_07_2024_963)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v27-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v27 5/9] Row pattern recognition patch (executor). @ 2024-12-30 23:53 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-30 23:53 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1845 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 58 + 4 files changed, 1935 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..2a06676572 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,33 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +#define STRSET_FROZEN (1 << 0) /* string is frozen */ +#define STRSET_DISCARDED (1 << 1) /* string is scheduled to be discarded */ +#define STRSET_MATCHED (1 << 2) /* string is confirmed to be matched + * with pattern */ + +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ + int *info; /* an array of information bit per StringInfo. + * see above */ +} StringSet; + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +214,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +226,60 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(WindowAggState *winstate, + StringSet *input_str_set); +static StringSet *generate_patterns(StringSet *input_str_set, + char *pattern, VariablePos *variable_pos, + char tail_pattern_initial); +static int add_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char c, char *pattern, char tail_pattern_initial, + int resultlen); +static int freeze_pattern(StringInfo old, int old_info, + StringSet *new_str_set, + char *pattern, int resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str, int info); +static StringInfo string_set_get(StringSet *string_set, int index, int *flag); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static VariablePos *variable_pos_build(WindowAggState *winstate); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +856,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +872,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +947,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1017,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1038,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1059,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) + != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) + == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1134,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1358,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2330,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2443,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2620,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2721,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2912,49 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + + /* + * Build variable_pos + */ + if (winstate->defineInitial) + winstate->variable_pos = variable_pos_build(winstate); + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2963,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3125,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3487,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3808,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3922,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4007,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4033,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4070,1430 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringSet *str_set; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + int init_size; + + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + + /* + * makeStringInfo creates initial data size to be 1024 bytes, which is + * too large for us because we only need the initial data as the + * number PATTERN variables (+null terminate), which is usually less + * than 10 bytes. So we reallocate the initial data size as small as + * the number of PATTERN variables. + */ + encoded_str = makeStringInfo(); + pfree(encoded_str->data); + init_size = list_length(winstate->patternVariableList) + 1; + encoded_str->data = (char *) palloc0(init_size); + encoded_str->maxlen = init_size; + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str, 0); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(winstate, str_set); + +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * + * Perform pattern matching using "pattern" against input_str_set. pattern is + * a regular expression string derived from PATTERN clause. Note that the + * regular expression string is prefixed by '^' and followed by initials + * represented in a same way as str_set. str_set is a set of StringInfo. Each + * StringInfo has a string comprising initials of pattern variable strings + * being true in a row. The initials are one of [a-z], parallel to the order + * of variable names in DEFINE clause. Suppose DEFINE has variables START, UP + * and DOWN. If PATTERN has START, UP+ and DOWN, then the initials in PATTERN + * will be 'a', 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(WindowAggState *winstate, StringSet *input_str_set) +{ + char *pattern; /* search regexp pattern */ + VariablePos *variable_pos; + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *new_str_set; + int new_str_size; + int len; + int info; + char tail_pattern_initial; + + /* + * Set last initial char to tail_pattern_initial if we can apply "tail + * pattern initial optimization". If the last regexp component in pattern + * is with '+' quatifier, set the initial to tail_pattern_initial. For + * example if pattern = "ab+", tail_pattern_initial will be 'b'. + * Otherwise, tail_pattern_initial is '\0'. + */ + pattern = winstate->pattern_str->data; + if (pattern[strlen(pattern) - 1] == '+') + tail_pattern_initial = pattern[strlen(pattern) - 2]; + else + tail_pattern_initial = '\0'; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + variable_pos = winstate->variable_pos; + new_str_set = generate_patterns(input_str_set, pattern, variable_pos, + tail_pattern_initial); + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + len = 0; + resultlen = 0; + set_size = string_set_get_size(input_str_set); + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index, &info); + if (s == NULL) + continue; /* no data */ + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + if (info & STRSET_DISCARDED) + continue; + + len = do_pattern_match(pattern, s->data, s->len); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * generate_patterns + * + * Generate all possible pattern variable name initials in 'input_str_set' as + * a set of StringInfo and return it. For example, if we have two rows having + * "ab" (row 0) and "ac" (row 1) in 'input str_set', returned StringSet will + * have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + * 'variable_pos' and 'tail_pattern_initial' are used for pruning + * optimization. + */ +static +StringSet * +generate_patterns(StringSet *input_str_set, char *pattern, + VariablePos *variable_pos, char tail_pattern_initial) +{ + StringSet *old_str_set, + *new_str_set; + int index; + int set_size; + int old_set_size; + int info; + int resultlen; + StringInfo str; + int i; + char *p; + + new_str_set = string_set_init(); + set_size = string_set_get_size(input_str_set); + if (set_size == 0) /* if there's no row in input, return empty + * set */ + return new_str_set; + + resultlen = 0; + + /* + * Generate initial new_string_set for input row 0. + */ + str = string_set_get(input_str_set, 0, &info); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new, 0); + p++; /* next pattern variable */ + } + + /* + * Generate new_string_set for each input row. + */ + for (index = 1; index < set_size; index++) + { + /* previous new str set now becomes old str set */ + old_str_set = new_str_set; + new_str_set = string_set_init(); /* create new string set */ + /* pick up input string */ + str = string_set_get(input_str_set, index, &info); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each row in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + char last_old_char; + int old_str_len; + int old_info; + StringInfo old; + + old = string_set_get(old_str_set, i, &old_info); + p = old->data; + old_str_len = old->len; + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Can this old set be discarded? */ + if (old_info & STRSET_DISCARDED) + continue; /* discard the old string */ + + /* Is this old set frozen? */ + else if (old_info & STRSET_FROZEN) + { + /* if shorter match. we can discard it */ + if (old_str_len < resultlen) + continue; /* discard the shorter string */ + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old, old_info); + old_str_set->str_set[i] = NULL; + continue; + } + + /* + * loop over each pattern variable initial char in the input set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable initial + * character position is greater than or equal to the old + * set's last pattern variable initial character position. For + * example, if the old set's last pattern variable initials + * are "ab", then the new pattern variable initial can be "b" + * or "c" but can not be "a", if the initials in PATTERN is + * something like "a b c" or "a b+ c+" etc. This optimization + * is possible when we only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + + /* + * Satisfied the condition. Add new pattern char to + * new_str_set if it looks good. + */ + resultlen = add_pattern(old, old_info, new_str_set, *p, + pattern, tail_pattern_initial, resultlen); + else + + /* + * The old_str did not satisfy the condition and it cannot + * be extended further. "Freeze" it. + */ + resultlen = freeze_pattern(old, old_info, + new_str_set, pattern, resultlen); + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + return new_str_set; +} + +/* + * add_pattern + * + * Make a copy of 'old' (along with 'old_info' flag) and add new pattern char + * 'c' to it. Then add it to 'new_str_set'. 'pattern' and + * 'tail_pattern_initial' is checked to determine whether the copy is worth to + * add to new_str_set or not. The match length (possibly longer than + * 'resultlen') is returned. + */ +static +int +add_pattern(StringInfo old, int old_info, StringSet *new_str_set, char c, + char *pattern, char tail_pattern_initial, int resultlen) +{ + StringInfo new; + int info; + int len; + + /* + * New char in the input row satisfies the condition above. + */ + new = makeStringInfo(); /* copy source string */ + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + + /* add pattern variable char */ + appendStringInfoChar(new, c); + + /* + * Adhoc optimization. If the first letter in the input string is in the + * head and second position and there's no associated quatifier '+', then + * we can dicard the input because there's no chance to expand the string + * further. + * + * For example, pattern "abc" cannot match "aa". + */ + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + destroyStringInfo(new); + return resultlen; + } + + info = old_info; + + /* + * Check if we can apply "tail pattern initial optimization". If the last + * regexp component in pattern has '+' quantifier, the component is set to + * the last pattern initial. For example if pattern is "ab+", + * tail_pattern_initial will become 'b'. Otherwise, tail_pattern_initial + * is '\0'. If the tail pattern initial optimization is possible, we do + * not need to apply regular expression match again. Suppose we have the + * previous string ended with "b" and the it was confirmed the regular + * expression match, then char 'b' can be added to the string without + * applying the regular expression match again. + */ + if (c == tail_pattern_initial) /* tail pattern initial optimization + * possible? */ + { + /* + * Is already confirmed to be matched with pattern? + */ + if ((info & STRSET_MATCHED) == 0) + { + /* not confirmed yet */ + len = do_pattern_match(pattern, new->data, new->len); + if (len > 0) + info = STRSET_MATCHED; /* set already confirmed flag */ + } + else + + /* + * already confirmed. Use the string length as the matching length + */ + len = new->len; + + /* update the longest match length if needed */ + if (len > resultlen) + resultlen = len; + } + + /* add new StringInfo to the string set */ + string_set_add(new_str_set, new, info); + + return resultlen; +} + +/* + * freeze_pattern + * + * "Freeze" 'old' (along with 'old_info' flag) and add it to + * 'new_str_set'. Frozen string is known to not be expanded further. The frozen + * string is check if it satisfies 'pattern'. If it does not, "discarded" + * mark is added. The discarded mark is also added if the match length is + * shorter than the current longest match length. The match length (possibly + * longer than 'resultlen') is returned. + */ +static +int +freeze_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char *pattern, int resultlen) +{ + int len; + StringInfo new; + int new_str_size; + int new_index; + + /* + * We are freezing this pattern string. If the pattern string length is + * shorter than the current longest string length, we don't need to keep + * it. + */ + if (old->len < resultlen) + return resultlen; + + if (old_info & STRSET_MATCHED) + /* we don't need to apply pattern match again */ + len = old->len; + else + { + /* apply pattern match */ + len = do_pattern_match(pattern, old->data, old->len); + if (len <= 0) + { + /* no match. we can discard it */ + return resultlen; + } + } + if (len < resultlen) + { + /* shorter match. we can discard it */ + return resultlen; + } + + /* + * Match length is the longest so far + */ + resultlen = len; /* remember the longest match */ + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* set frozen mark */ + string_set_add(new_str_set, new, STRSET_FROZEN); + + /* + * Search new_str_set to find out frozen entries that have shorter match + * length. Mark them as "discard" so that they are discarded in the next + * round. + */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + int info; + + new = string_set_get(new_str_set, new_index, &info); + + /* + * If this is frozen and is not longer than the current longest match + * length, we don't need to keep this. + */ + if (info & STRSET_FROZEN && new->len < resultlen) + { + /* + * mark this set to discard in the next round + */ + info |= STRSET_DISCARDED; + new_str_set->info[new_index] = info; + } + } + return resultlen; +} + +/* + * do_pattern_match + * + * Perform pattern match using 'pattern' against 'encoded_str' whose length is + * 'len' bytes (without null terminate). Returns matching number of rows if + * matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t *regcache = NULL; + static regex_t preg; + static char patbuf[1024]; /* most recent 'pattern' is cached here */ + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + /* + * Compile regexp if cache does not exist or existing cache is not same as + * "pattern". + */ + if (strcmp(patbuf, pattern)) + { + /* + * The compiled re must live in top memory context because patbuf is + * static data. + */ + MemoryContext oldContext = MemoryContextSwitchTo(TopMemoryContext); + + if (regcache != NULL) + pg_regfree(regcache); /* free previous re */ + + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + MemoryContextSwitchTo(oldContext); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + + /* save cache */ + regcache = &preg; + strncpy(patbuf, pattern, sizeof(patbuf)); + } + + data = (pg_wchar *) palloc((len + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +/* + * evaluate_pattern + * + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->info = palloc0(set_size * sizeof(int)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str, int info) +{ + Size set_size; + Size old_set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + old_set_size = set_size; + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->info = repalloc0(string_set->info, + old_set_size * sizeof(int), + set_size * sizeof(int)); + string_set->set_size = set_size; + } + + string_set->info[string_set->set_index] = info; + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index, int *info) +{ + *info = 0; + + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + *info = string_set->info[index]; + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->info); + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_build + * + * Build VariablePos structure and return it. + */ +static +VariablePos * +variable_pos_build(WindowAggState *winstate) +{ + VariablePos *variable_pos; + StringInfo pattern_str; + int initial_index = 0; + ListCell *lc1, + *lc2; + + variable_pos = winstate->variable_pos = variable_pos_init(); + pattern_str = winstate->pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + return variable_pos; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1590b64392..f96782fd6a 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,37 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + +/* + * Allowed PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postions in PATTERN */ +} VariablePos; + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2675,21 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + VariablePos *variable_pos; /* list of pattern variable positions */ + StringInfo pattern_str; /* PATTERN initials */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2717,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Dec_31_08_57_07_2024_963)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v27-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH v27 5/9] Row pattern recognition patch (executor). @ 2024-12-30 23:53 Tatsuo Ishii <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Tatsuo Ishii @ 2024-12-30 23:53 UTC (permalink / raw) --- src/backend/executor/nodeWindowAgg.c | 1845 +++++++++++++++++++++++++- src/backend/utils/adt/windowfuncs.c | 37 +- src/include/catalog/pg_proc.dat | 6 + src/include/nodes/execnodes.h | 58 + 4 files changed, 1935 insertions(+), 11 deletions(-) diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c index 70a7025818..2a06676572 100644 --- a/src/backend/executor/nodeWindowAgg.c +++ b/src/backend/executor/nodeWindowAgg.c @@ -36,6 +36,7 @@ #include "access/htup_details.h" #include "catalog/objectaccess.h" #include "catalog/pg_aggregate.h" +#include "catalog/pg_collation_d.h" #include "catalog/pg_proc.h" #include "executor/executor.h" #include "executor/nodeWindowAgg.h" @@ -45,9 +46,11 @@ #include "optimizer/optimizer.h" #include "parser/parse_agg.h" #include "parser/parse_coerce.h" +#include "regex/regex.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/datum.h" +#include "utils/fmgroids.h" #include "utils/expandeddatum.h" #include "utils/lsyscache.h" #include "utils/memutils.h" @@ -159,6 +162,33 @@ typedef struct WindowStatePerAggData bool restart; /* need to restart this agg in this cycle? */ } WindowStatePerAggData; +/* + * Set of StringInfo. Used in RPR. + */ +#define STRSET_FROZEN (1 << 0) /* string is frozen */ +#define STRSET_DISCARDED (1 << 1) /* string is scheduled to be discarded */ +#define STRSET_MATCHED (1 << 2) /* string is confirmed to be matched + * with pattern */ + +typedef struct StringSet +{ + StringInfo *str_set; + Size set_size; /* current array allocation size in number of + * items */ + int set_index; /* current used size */ + int *info; /* an array of information bit per StringInfo. + * see above */ +} StringSet; + +/* + * Structure used by check_rpr_navigation() and rpr_navigation_walker(). + */ +typedef struct NavigationInfo +{ + bool is_prev; /* true if PREV */ + int num_vars; /* number of var nodes */ +} NavigationInfo; + static void initialize_windowaggregate(WindowAggState *winstate, WindowStatePerFunc perfuncstate, WindowStatePerAgg peraggstate); @@ -184,6 +214,7 @@ static void release_partition(WindowAggState *winstate); static int row_is_in_frame(WindowAggState *winstate, int64 pos, TupleTableSlot *slot); + static void update_frameheadpos(WindowAggState *winstate); static void update_frametailpos(WindowAggState *winstate); static void update_grouptailpos(WindowAggState *winstate); @@ -195,9 +226,60 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype); static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1, TupleTableSlot *slot2); + +static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout); static bool window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot); +static void attno_map(Node *node); +static bool attno_map_walker(Node *node, void *context); +static int row_is_in_reduced_frame(WindowObject winobj, int64 pos); +static bool rpr_is_defined(WindowAggState *winstate); + +static void create_reduced_frame_map(WindowAggState *winstate); +static int get_reduced_frame_map(WindowAggState *winstate, int64 pos); +static void register_reduced_frame_map(WindowAggState *winstate, int64 pos, + int val); +static void clear_reduced_frame_map(WindowAggState *winstate); +static void update_reduced_frame(WindowObject winobj, int64 pos); + +static int64 evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result); + +static bool get_slots(WindowObject winobj, int64 current_pos); + +static int search_str_set(WindowAggState *winstate, + StringSet *input_str_set); +static StringSet *generate_patterns(StringSet *input_str_set, + char *pattern, VariablePos *variable_pos, + char tail_pattern_initial); +static int add_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char c, char *pattern, char tail_pattern_initial, + int resultlen); +static int freeze_pattern(StringInfo old, int old_info, + StringSet *new_str_set, + char *pattern, int resultlen); +static char pattern_initial(WindowAggState *winstate, char *vname); +static int do_pattern_match(char *pattern, char *encoded_str, int len); + +static StringSet *string_set_init(void); +static void string_set_add(StringSet *string_set, StringInfo str, int info); +static StringInfo string_set_get(StringSet *string_set, int index, int *flag); +static int string_set_get_size(StringSet *string_set); +static void string_set_discard(StringSet *string_set); +static VariablePos *variable_pos_init(void); +static void variable_pos_register(VariablePos *variable_pos, char initial, + int pos); +static bool variable_pos_compare(VariablePos *variable_pos, + char initial1, char initial2); +static int variable_pos_fetch(VariablePos *variable_pos, char initial, + int index); +static VariablePos *variable_pos_build(WindowAggState *winstate); + +static void check_rpr_navigation(Node *node, bool is_prev); +static bool rpr_navigation_walker(Node *node, void *context); /* * initialize_windowaggregate @@ -774,10 +856,12 @@ eval_windowaggregates(WindowAggState *winstate) * transition function, or * - we have an EXCLUSION clause, or * - if the new frame doesn't overlap the old one + * - if RPR is enabled * * Note that we don't strictly need to restart in the last case, but if * we're going to remove all rows from the aggregation anyway, a restart * surely is faster. + * we restart aggregation too. *---------- */ numaggs_restart = 0; @@ -788,7 +872,8 @@ eval_windowaggregates(WindowAggState *winstate) (winstate->aggregatedbase != winstate->frameheadpos && !OidIsValid(peraggstate->invtransfn_oid)) || (winstate->frameOptions & FRAMEOPTION_EXCLUSION) || - winstate->aggregatedupto <= winstate->frameheadpos) + winstate->aggregatedupto <= winstate->frameheadpos || + rpr_is_defined(winstate)) { peraggstate->restart = true; numaggs_restart++; @@ -862,7 +947,22 @@ eval_windowaggregates(WindowAggState *winstate) * head, so that tuplestore can discard unnecessary rows. */ if (agg_winobj->markptr >= 0) - WinSetMarkPosition(agg_winobj, winstate->frameheadpos); + { + int64 markpos = winstate->frameheadpos; + + if (rpr_is_defined(winstate)) + { + /* + * If RPR is used, it is possible PREV wants to look at the + * previous row. So the mark pos should be frameheadpos - 1 + * unless it is below 0. + */ + markpos -= 1; + if (markpos < 0) + markpos = 0; + } + WinSetMarkPosition(agg_winobj, markpos); + } /* * Now restart the aggregates that require it. @@ -917,6 +1017,14 @@ eval_windowaggregates(WindowAggState *winstate) { winstate->aggregatedupto = winstate->frameheadpos; ExecClearTuple(agg_row_slot); + + /* + * If RPR is defined, we do not use aggregatedupto_nonrestarted. To + * avoid assertion failure below, we reset aggregatedupto_nonrestarted + * to frameheadpos. + */ + if (rpr_is_defined(winstate)) + aggregatedupto_nonrestarted = winstate->frameheadpos; } /* @@ -930,6 +1038,12 @@ eval_windowaggregates(WindowAggState *winstate) { int ret; +#ifdef RPR_DEBUG + elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + /* Fetch next row if we didn't already */ if (TupIsNull(agg_row_slot)) { @@ -945,9 +1059,53 @@ eval_windowaggregates(WindowAggState *winstate) ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot); if (ret < 0) break; + if (ret == 0) goto next_tuple; + if (rpr_is_defined(winstate)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT, + get_reduced_frame_map(winstate, + winstate->aggregatedupto), + winstate->aggregatedupto, + winstate->aggregatedbase); +#endif + + /* + * If the row status at currentpos is already decided and current + * row status is not decided yet, it means we passed the last + * reduced frame. Time to break the loop. + */ + if (get_reduced_frame_map(winstate, winstate->currentpos) + != RF_NOT_DETERMINED && + get_reduced_frame_map(winstate, winstate->aggregatedupto) + == RF_NOT_DETERMINED) + break; + + /* + * Otherwise we need to calculate the reduced frame. + */ + ret = row_is_in_reduced_frame(winstate->agg_winobj, + winstate->aggregatedupto); + if (ret == -1) /* unmatched row */ + break; + + /* + * Check if current row needs to be skipped due to no match. + */ + if (get_reduced_frame_map(winstate, + winstate->aggregatedupto) == RF_SKIPPED && + winstate->aggregatedupto == winstate->aggregatedbase) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "skip current row for aggregation"); +#endif + break; + } + } + /* Set tuple context for evaluation of aggregate arguments */ winstate->tmpcontext->ecxt_outertuple = agg_row_slot; @@ -976,6 +1134,7 @@ next_tuple: ExecClearTuple(agg_row_slot); } + /* The frame's end is not supposed to move backwards, ever */ Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto); @@ -1199,6 +1358,7 @@ begin_partition(WindowAggState *winstate) winstate->framehead_valid = false; winstate->frametail_valid = false; winstate->grouptail_valid = false; + create_reduced_frame_map(winstate); winstate->spooled_rows = 0; winstate->currentpos = 0; winstate->frameheadpos = 0; @@ -2170,6 +2330,11 @@ ExecWindowAgg(PlanState *pstate) CHECK_FOR_INTERRUPTS(); +#ifdef RPR_DEBUG + elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT, + winstate->currentpos); +#endif + if (winstate->status == WINDOWAGG_DONE) return NULL; @@ -2278,6 +2443,17 @@ ExecWindowAgg(PlanState *pstate) /* don't evaluate the window functions when we're in pass-through mode */ if (winstate->status == WINDOWAGG_RUN) { + /* + * If RPR is defined and skip mode is next row, we need to clear + * existing reduced frame info so that we newly calculate the info + * starting from current row. + */ + if (rpr_is_defined(winstate)) + { + if (winstate->rpSkipTo == ST_NEXT_ROW) + clear_reduced_frame_map(winstate); + } + /* * Evaluate true window functions */ @@ -2444,6 +2620,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) TupleDesc scanDesc; ListCell *l; + TargetEntry *te; + Expr *expr; + /* check for unsupported flags */ Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK))); @@ -2542,6 +2721,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc, &TTSOpsMinimalTuple); + winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + + winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc, + &TTSOpsMinimalTuple); + winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot); + /* * create frame head and tail slots only if needed (must create slots in * exactly the same cases that update_frameheadpos and update_frametailpos @@ -2723,6 +2912,49 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) winstate->inRangeAsc = node->inRangeAsc; winstate->inRangeNullsFirst = node->inRangeNullsFirst; + /* Set up SKIP TO type */ + winstate->rpSkipTo = node->rpSkipTo; + /* Set up row pattern recognition PATTERN clause */ + winstate->patternVariableList = node->patternVariable; + winstate->patternRegexpList = node->patternRegexp; + + /* Set up row pattern recognition DEFINE clause */ + winstate->defineInitial = node->defineInitial; + winstate->defineVariableList = NIL; + winstate->defineClauseList = NIL; + if (node->defineClause != NIL) + { + /* + * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot. + */ + foreach(l, node->defineClause) + { + char *name; + ExprState *exps; + + te = lfirst(l); + name = te->resname; + expr = te->expr; + +#ifdef RPR_DEBUG + elog(DEBUG1, "defineVariable name: %s", name); +#endif + winstate->defineVariableList = + lappend(winstate->defineVariableList, + makeString(pstrdup(name))); + attno_map((Node *) expr); + exps = ExecInitExpr(expr, (PlanState *) winstate); + winstate->defineClauseList = + lappend(winstate->defineClauseList, exps); + } + } + + /* + * Build variable_pos + */ + if (winstate->defineInitial) + winstate->variable_pos = variable_pos_build(winstate); + winstate->all_first = true; winstate->partition_spooled = false; winstate->more_partitions = false; @@ -2731,6 +2963,111 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags) return winstate; } +/* + * Rewrite varno of Var nodes that are the argument of PREV/NET so that they + * see scan tuple (PREV) or inner tuple (NEXT). Also we check the arguments + * of PREV/NEXT include at least 1 column reference. This is required by the + * SQL standard. + */ +static void +attno_map(Node *node) +{ + (void) expression_tree_walker(node, attno_map_walker, NULL); +} + +static bool +attno_map_walker(Node *node, void *context) +{ + FuncExpr *func; + int nargs; + bool is_prev; + + if (node == NULL) + return false; + + if (IsA(node, FuncExpr)) + { + func = (FuncExpr *) node; + + if (func->funcid == F_PREV || func->funcid == F_NEXT) + { + /* + * The SQL standard allows to have two more arguments form of + * PREV/NEXT. But currently we allow only 1 argument form. + */ + nargs = list_length(func->args); + if (list_length(func->args) != 1) + elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args", + func->funcid, nargs); + + /* + * Check expr of PREV/NEXT aruguments and replace varno. + */ + is_prev = (func->funcid == F_PREV) ? true : false; + check_rpr_navigation(node, is_prev); + } + } + return expression_tree_walker(node, attno_map_walker, NULL); +} + +/* + * Rewrite varno of Var of RPR navigation operations (PREV/NEXT). + * If is_prev is true, we take care PREV, otherwise NEXT. + */ +static void +check_rpr_navigation(Node *node, bool is_prev) +{ + NavigationInfo context; + + context.is_prev = is_prev; + context.num_vars = 0; + (void) expression_tree_walker(node, rpr_navigation_walker, &context); + if (context.num_vars < 1) + ereport(ERROR, + errmsg("row pattern navigation operation's argument must include at least one column reference")); +} + +static bool +rpr_navigation_walker(Node *node, void *context) +{ + NavigationInfo *nav = (NavigationInfo *) context; + + if (node == NULL) + return false; + + switch (nodeTag(node)) + { + case T_Var: + { + Var *var = (Var *) node; + + nav->num_vars++; + + if (nav->is_prev) + { + /* + * Rewrite varno from OUTER_VAR to regular var no so that + * the var references scan tuple. + */ + var->varno = var->varnosyn; + } + else + var->varno = INNER_VAR; + } + break; + case T_Const: + case T_FuncExpr: + case T_OpExpr: + break; + + default: + ereport(ERROR, + errmsg("row pattern navigation operation's argument includes unsupported expression")); + } + return expression_tree_walker(node, rpr_navigation_walker, context); +} + + /* ----------------- * ExecEndWindowAgg * ----------------- @@ -2788,6 +3125,8 @@ ExecReScanWindowAgg(WindowAggState *node) ExecClearTuple(node->agg_row_slot); ExecClearTuple(node->temp_slot_1); ExecClearTuple(node->temp_slot_2); + ExecClearTuple(node->prev_slot); + ExecClearTuple(node->next_slot); if (node->framehead_slot) ExecClearTuple(node->framehead_slot); if (node->frametail_slot) @@ -3148,7 +3487,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot) return false; if (pos < winobj->markpos) - elog(ERROR, "cannot fetch row before WindowObject's mark position"); + elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT, + pos, winobj->markpos); oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory); @@ -3468,14 +3808,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, WindowAggState *winstate; ExprContext *econtext; TupleTableSlot *slot; - int64 abs_pos; - int64 mark_pos; Assert(WindowObjectIsValid(winobj)); winstate = winobj->winstate; econtext = winstate->ss.ps.ps_ExprContext; slot = winstate->temp_slot_1; + if (WinGetSlotInFrame(winobj, slot, + relpos, seektype, set_mark, + isnull, isout) == 0) + { + econtext->ecxt_outertuple = slot; + return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), + econtext, isnull); + } + + if (isout) + *isout = true; + *isnull = true; + return (Datum) 0; +} + +/* + * WinGetSlotInFrame + * slot: TupleTableSlot to store the result + * relpos: signed rowcount offset from the seek position + * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL + * set_mark: If the row is found/in frame and set_mark is true, the mark is + * moved to the row as a side-effect. + * isnull: output argument, receives isnull status of result + * isout: output argument, set to indicate whether target row position + * is out of frame (can pass NULL if caller doesn't care about this) + * + * Returns 0 if we successfullt got the slot. false if out of frame. + * (also isout is set) + */ +static int +WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot, + int relpos, int seektype, bool set_mark, + bool *isnull, bool *isout) +{ + WindowAggState *winstate; + int64 abs_pos; + int64 mark_pos; + int num_reduced_frame; + + Assert(WindowObjectIsValid(winobj)); + winstate = winobj->winstate; + switch (seektype) { case WINDOW_SEEK_CURRENT: @@ -3542,11 +3922,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, winstate->frameOptions); break; } + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + if (relpos >= num_reduced_frame) + goto out_of_frame; break; case WINDOW_SEEK_TAIL: /* rejecting relpos > 0 is easy and simplifies code below */ if (relpos > 0) goto out_of_frame; + + /* + * RPR cares about frame head pos. Need to call + * update_frameheadpos + */ + update_frameheadpos(winstate); + update_frametailpos(winstate); abs_pos = winstate->frametailpos - 1 + relpos; @@ -3613,6 +4007,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, mark_pos = 0; /* keep compiler quiet */ break; } + + num_reduced_frame = row_is_in_reduced_frame(winobj, + winstate->frameheadpos + relpos); + if (num_reduced_frame < 0) + goto out_of_frame; + else if (num_reduced_frame > 0) + abs_pos = winstate->frameheadpos + relpos + + num_reduced_frame - 1; break; default: elog(ERROR, "unrecognized window seek type: %d", seektype); @@ -3631,15 +4033,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno, *isout = false; if (set_mark) WinSetMarkPosition(winobj, mark_pos); - econtext->ecxt_outertuple = slot; - return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), - econtext, isnull); + return 0; out_of_frame: if (isout) *isout = true; *isnull = true; - return (Datum) 0; + return -1; } /* @@ -3670,3 +4070,1430 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull) return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno), econtext, isnull); } + +/* + * rpr_is_defined + * return true if Row pattern recognition is defined. + */ +static +bool +rpr_is_defined(WindowAggState *winstate) +{ + return winstate->patternVariableList != NIL; +} + +/* + * ----------------- + * row_is_in_reduced_frame + * Determine whether a row is in the current row's reduced window frame + * according to row pattern matching + * + * The row must has been already determined that it is in a full window frame + * and fetched it into slot. + * + * Returns: + * = 0, RPR is not defined. + * >0, if the row is the first in the reduced frame. Return the number of rows + * in the reduced frame. + * -1, if the row is unmatched row + * -2, if the row is in the reduced frame but needed to be skipped because of + * AFTER MATCH SKIP PAST LAST ROW + * ----------------- + */ +static +int +row_is_in_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + int state; + int rtn; + + if (!rpr_is_defined(winstate)) + { + /* + * RPR is not defined. Assume that we are always in the the reduced + * window frame. + */ + rtn = 0; +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; + } + + state = get_reduced_frame_map(winstate, pos); + + if (state == RF_NOT_DETERMINED) + { + update_frameheadpos(winstate); + update_reduced_frame(winobj, pos); + } + + state = get_reduced_frame_map(winstate, pos); + + switch (state) + { + int64 i; + int num_reduced_rows; + + case RF_FRAME_HEAD: + num_reduced_rows = 1; + for (i = pos + 1; + get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++) + num_reduced_rows++; + rtn = num_reduced_rows; + break; + + case RF_SKIPPED: + rtn = -2; + break; + + case RF_UNMATCHED: + rtn = -1; + break; + + default: + elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT, + state, pos); + break; + } + +#ifdef RPR_DEBUG + elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT, + rtn, pos); +#endif + return rtn; +} + +#define REDUCED_FRAME_MAP_INIT_SIZE 1024L + +/* + * create_reduced_frame_map + * Create reduced frame map + */ +static +void +create_reduced_frame_map(WindowAggState *winstate) +{ + winstate->reduced_frame_map = + MemoryContextAlloc(winstate->partcontext, + REDUCED_FRAME_MAP_INIT_SIZE); + winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE; + clear_reduced_frame_map(winstate); +} + +/* + * clear_reduced_frame_map + * Clear reduced frame map + */ +static +void +clear_reduced_frame_map(WindowAggState *winstate) +{ + Assert(winstate->reduced_frame_map != NULL); + MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED, + winstate->alloc_sz); +} + +/* + * get_reduced_frame_map + * Get reduced frame map specified by pos + */ +static +int +get_reduced_frame_map(WindowAggState *winstate, int64 pos) +{ + Assert(winstate->reduced_frame_map != NULL); + Assert(pos >= 0); + + /* + * If pos is not in the reduced frame map, it means that any info + * regarding the pos has not been registered yet. So we return + * RF_NOT_DETERMINED. + */ + if (pos >= winstate->alloc_sz) + return RF_NOT_DETERMINED; + + return winstate->reduced_frame_map[pos]; +} + +/* + * register_reduced_frame_map + * Add/replace reduced frame map member at pos. + * If there's no enough space, expand the map. + */ +static +void +register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val) +{ + int64 realloc_sz; + + Assert(winstate->reduced_frame_map != NULL); + + if (pos < 0) + elog(ERROR, "wrong pos: " INT64_FORMAT, pos); + + if (pos > winstate->alloc_sz - 1) + { + realloc_sz = winstate->alloc_sz * 2; + + winstate->reduced_frame_map = + repalloc(winstate->reduced_frame_map, realloc_sz); + + MemSet(winstate->reduced_frame_map + winstate->alloc_sz, + RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz); + + winstate->alloc_sz = realloc_sz; + } + + winstate->reduced_frame_map[pos] = val; +} + +/* + * update_reduced_frame + * Update reduced frame info. + */ +static +void +update_reduced_frame(WindowObject winobj, int64 pos) +{ + WindowAggState *winstate = winobj->winstate; + ListCell *lc1, + *lc2; + bool expression_result; + int num_matched_rows; + int64 original_pos; + bool anymatch; + StringInfo encoded_str; + StringSet *str_set; + bool greedy = false; + int64 result_pos, + i; + + /* + * Set of pattern variables evaluated to true. Each character corresponds + * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In + * this case at row 0 A and B are true, and A and C are true in row 1. + */ + + /* initialize pattern variables set */ + str_set = string_set_init(); + + /* save original pos */ + original_pos = pos; + + /* + * Check if the pattern does not include any greedy quantifier. If it does + * not, we can just apply the pattern to each row. If it succeeds, we are + * done. + */ + foreach(lc1, winstate->patternRegexpList) + { + char *quantifier = strVal(lfirst(lc1)); + + if (*quantifier == '+' || *quantifier == '*') + { + greedy = true; + break; + } + } + + /* + * Non greedy case + */ + if (!greedy) + { + num_matched_rows = 0; + + foreach(lc1, winstate->patternVariableList) + { + char *vname = strVal(lfirst(lc1)); + + encoded_str = makeStringInfo(); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s", + pos, vname); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + destroyStringInfo(encoded_str); + + if (!expression_result || result_pos < 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is false or out of frame"); +#endif + register_reduced_frame_map(winstate, original_pos, + RF_UNMATCHED); + return; + } + /* move to next row */ + pos++; + num_matched_rows++; + } +#ifdef RPR_DEBUG + elog(DEBUG1, "pattern matched"); +#endif + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + return; + } + + /* + * Greedy quantifiers included. Loop over until none of pattern matches or + * encounters end of frame. + */ + for (;;) + { + int init_size; + + result_pos = -1; + + /* + * Loop over each PATTERN variable. + */ + anymatch = false; + + /* + * makeStringInfo creates initial data size to be 1024 bytes, which is + * too large for us because we only need the initial data as the + * number PATTERN variables (+null terminate), which is usually less + * than 10 bytes. So we reallocate the initial data size as small as + * the number of PATTERN variables. + */ + encoded_str = makeStringInfo(); + pfree(encoded_str->data); + init_size = list_length(winstate->patternVariableList) + 1; + encoded_str->data = (char *) palloc0(init_size); + encoded_str->maxlen = init_size; + + forboth(lc1, winstate->patternVariableList, lc2, + winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); +#ifdef RPR_DEBUG + char *quantifier = strVal(lfirst(lc2)); + + elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s", + pos, vname, quantifier); +#endif + expression_result = false; + + /* evaluate row pattern against current row */ + result_pos = evaluate_pattern(winobj, pos, vname, + encoded_str, &expression_result); + if (expression_result) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "expression result is true"); +#endif + anymatch = true; + } + + /* + * If out of frame, we are done. + */ + if (result_pos < 0) + break; + } + + if (!anymatch) + { + /* none of patterns matched. */ + break; + } + + string_set_add(str_set, encoded_str, 0); + +#ifdef RPR_DEBUG + elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s", + encoded_str->data); +#endif + + /* move to next row */ + pos++; + + if (result_pos < 0) + { + /* out of frame */ + break; + } + } + + if (string_set_get_size(str_set) == 0) + { + /* no match found in the first row */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + destroyStringInfo(encoded_str); + return; + } + +#ifdef RPR_DEBUG + elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s", + pos, encoded_str->data); +#endif + + /* look for matching pattern variable sequence */ +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set started"); +#endif + num_matched_rows = search_str_set(winstate, str_set); + +#ifdef RPR_DEBUG + elog(DEBUG1, "search_str_set returns: %d", num_matched_rows); +#endif + string_set_discard(str_set); + + /* + * We are at the first row in the reduced frame. Save the number of + * matched rows as the number of rows in the reduced frame. + */ + if (num_matched_rows <= 0) + { + /* no match */ + register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED); + } + else + { + register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD); + + for (i = original_pos + 1; i < original_pos + num_matched_rows; i++) + { + register_reduced_frame_map(winstate, i, RF_SKIPPED); + } + } + + return; +} + +/* + * search_str_set + * + * Perform pattern matching using "pattern" against input_str_set. pattern is + * a regular expression string derived from PATTERN clause. Note that the + * regular expression string is prefixed by '^' and followed by initials + * represented in a same way as str_set. str_set is a set of StringInfo. Each + * StringInfo has a string comprising initials of pattern variable strings + * being true in a row. The initials are one of [a-z], parallel to the order + * of variable names in DEFINE clause. Suppose DEFINE has variables START, UP + * and DOWN. If PATTERN has START, UP+ and DOWN, then the initials in PATTERN + * will be 'a', 'b' and 'c'. The "pattern" will be "^ab+c". + * + * variable_pos is an array representing the order of pattern variable string + * initials in PATTERN clause. For example initial 'a' potion is in + * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP" + * (UP appears twice), then "UP" (initial is 'b') has two position 1 and + * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and + * variable_pos[1].pos[1] = 3. + * + * Returns the longest number of the matching rows (greedy matching) if + * quatifier '+' or '*' is included in "pattern". + */ +static +int +search_str_set(WindowAggState *winstate, StringSet *input_str_set) +{ + char *pattern; /* search regexp pattern */ + VariablePos *variable_pos; + int set_size; /* number of rows in the set */ + int resultlen; + int index; + StringSet *new_str_set; + int new_str_size; + int len; + int info; + char tail_pattern_initial; + + /* + * Set last initial char to tail_pattern_initial if we can apply "tail + * pattern initial optimization". If the last regexp component in pattern + * is with '+' quatifier, set the initial to tail_pattern_initial. For + * example if pattern = "ab+", tail_pattern_initial will be 'b'. + * Otherwise, tail_pattern_initial is '\0'. + */ + pattern = winstate->pattern_str->data; + if (pattern[strlen(pattern) - 1] == '+') + tail_pattern_initial = pattern[strlen(pattern) - 2]; + else + tail_pattern_initial = '\0'; + + /* + * Generate all possible pattern variable name initials as a set of + * StringInfo named "new_str_set". For example, if we have two rows + * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set + * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + */ + variable_pos = winstate->variable_pos; + new_str_set = generate_patterns(input_str_set, pattern, variable_pos, + tail_pattern_initial); + + /* + * Perform pattern matching to find out the longest match. + */ + new_str_size = string_set_get_size(new_str_set); + len = 0; + resultlen = 0; + set_size = string_set_get_size(input_str_set); + + for (index = 0; index < new_str_size; index++) + { + StringInfo s; + + s = string_set_get(new_str_set, index, &info); + if (s == NULL) + continue; /* no data */ + + /* + * If the string is scheduled to be discarded, we just disregard it. + */ + if (info & STRSET_DISCARDED) + continue; + + len = do_pattern_match(pattern, s->data, s->len); + if (len > resultlen) + { + /* remember the longest match */ + resultlen = len; + + /* + * If the size of result set is equal to the number of rows in the + * set, we are done because it's not possible that the number of + * matching rows exceeds the number of rows in the set. + */ + if (resultlen >= set_size) + break; + } + } + + /* we no longer need new string set */ + string_set_discard(new_str_set); + + return resultlen; +} + +/* + * generate_patterns + * + * Generate all possible pattern variable name initials in 'input_str_set' as + * a set of StringInfo and return it. For example, if we have two rows having + * "ab" (row 0) and "ac" (row 1) in 'input str_set', returned StringSet will + * have set of StringInfo "aa", "ac", "ba" and "bc" in the end. + * 'variable_pos' and 'tail_pattern_initial' are used for pruning + * optimization. + */ +static +StringSet * +generate_patterns(StringSet *input_str_set, char *pattern, + VariablePos *variable_pos, char tail_pattern_initial) +{ + StringSet *old_str_set, + *new_str_set; + int index; + int set_size; + int old_set_size; + int info; + int resultlen; + StringInfo str; + int i; + char *p; + + new_str_set = string_set_init(); + set_size = string_set_get_size(input_str_set); + if (set_size == 0) /* if there's no row in input, return empty + * set */ + return new_str_set; + + resultlen = 0; + + /* + * Generate initial new_string_set for input row 0. + */ + str = string_set_get(input_str_set, 0, &info); + p = str->data; + + /* + * Loop over each new pattern variable char. + */ + while (*p) + { + StringInfo new = makeStringInfo(); + + /* add pattern variable char */ + appendStringInfoChar(new, *p); + /* add new one to string set */ + string_set_add(new_str_set, new, 0); + p++; /* next pattern variable */ + } + + /* + * Generate new_string_set for each input row. + */ + for (index = 1; index < set_size; index++) + { + /* previous new str set now becomes old str set */ + old_str_set = new_str_set; + new_str_set = string_set_init(); /* create new string set */ + /* pick up input string */ + str = string_set_get(input_str_set, index, &info); + old_set_size = string_set_get_size(old_str_set); + + /* + * Loop over each row in the previous result set. + */ + for (i = 0; i < old_set_size; i++) + { + char last_old_char; + int old_str_len; + int old_info; + StringInfo old; + + old = string_set_get(old_str_set, i, &old_info); + p = old->data; + old_str_len = old->len; + if (old_str_len > 0) + last_old_char = p[old_str_len - 1]; + else + last_old_char = '\0'; + + /* Can this old set be discarded? */ + if (old_info & STRSET_DISCARDED) + continue; /* discard the old string */ + + /* Is this old set frozen? */ + else if (old_info & STRSET_FROZEN) + { + /* if shorter match. we can discard it */ + if (old_str_len < resultlen) + continue; /* discard the shorter string */ + + /* move the old set to new_str_set */ + string_set_add(new_str_set, old, old_info); + old_str_set->str_set[i] = NULL; + continue; + } + + /* + * loop over each pattern variable initial char in the input set. + */ + for (p = str->data; *p; p++) + { + /* + * Optimization. Check if the row's pattern variable initial + * character position is greater than or equal to the old + * set's last pattern variable initial character position. For + * example, if the old set's last pattern variable initials + * are "ab", then the new pattern variable initial can be "b" + * or "c" but can not be "a", if the initials in PATTERN is + * something like "a b c" or "a b+ c+" etc. This optimization + * is possible when we only allow "+" quantifier. + */ + if (variable_pos_compare(variable_pos, last_old_char, *p)) + + /* + * Satisfied the condition. Add new pattern char to + * new_str_set if it looks good. + */ + resultlen = add_pattern(old, old_info, new_str_set, *p, + pattern, tail_pattern_initial, resultlen); + else + + /* + * The old_str did not satisfy the condition and it cannot + * be extended further. "Freeze" it. + */ + resultlen = freeze_pattern(old, old_info, + new_str_set, pattern, resultlen); + } + } + /* we no longer need old string set */ + string_set_discard(old_str_set); + } + return new_str_set; +} + +/* + * add_pattern + * + * Make a copy of 'old' (along with 'old_info' flag) and add new pattern char + * 'c' to it. Then add it to 'new_str_set'. 'pattern' and + * 'tail_pattern_initial' is checked to determine whether the copy is worth to + * add to new_str_set or not. The match length (possibly longer than + * 'resultlen') is returned. + */ +static +int +add_pattern(StringInfo old, int old_info, StringSet *new_str_set, char c, + char *pattern, char tail_pattern_initial, int resultlen) +{ + StringInfo new; + int info; + int len; + + /* + * New char in the input row satisfies the condition above. + */ + new = makeStringInfo(); /* copy source string */ + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + + /* add pattern variable char */ + appendStringInfoChar(new, c); + + /* + * Adhoc optimization. If the first letter in the input string is in the + * head and second position and there's no associated quatifier '+', then + * we can dicard the input because there's no chance to expand the string + * further. + * + * For example, pattern "abc" cannot match "aa". + */ + if (pattern[1] == new->data[0] && + pattern[1] == new->data[1] && + pattern[2] != '+' && + pattern[1] != pattern[2]) + { + destroyStringInfo(new); + return resultlen; + } + + info = old_info; + + /* + * Check if we can apply "tail pattern initial optimization". If the last + * regexp component in pattern has '+' quantifier, the component is set to + * the last pattern initial. For example if pattern is "ab+", + * tail_pattern_initial will become 'b'. Otherwise, tail_pattern_initial + * is '\0'. If the tail pattern initial optimization is possible, we do + * not need to apply regular expression match again. Suppose we have the + * previous string ended with "b" and the it was confirmed the regular + * expression match, then char 'b' can be added to the string without + * applying the regular expression match again. + */ + if (c == tail_pattern_initial) /* tail pattern initial optimization + * possible? */ + { + /* + * Is already confirmed to be matched with pattern? + */ + if ((info & STRSET_MATCHED) == 0) + { + /* not confirmed yet */ + len = do_pattern_match(pattern, new->data, new->len); + if (len > 0) + info = STRSET_MATCHED; /* set already confirmed flag */ + } + else + + /* + * already confirmed. Use the string length as the matching length + */ + len = new->len; + + /* update the longest match length if needed */ + if (len > resultlen) + resultlen = len; + } + + /* add new StringInfo to the string set */ + string_set_add(new_str_set, new, info); + + return resultlen; +} + +/* + * freeze_pattern + * + * "Freeze" 'old' (along with 'old_info' flag) and add it to + * 'new_str_set'. Frozen string is known to not be expanded further. The frozen + * string is check if it satisfies 'pattern'. If it does not, "discarded" + * mark is added. The discarded mark is also added if the match length is + * shorter than the current longest match length. The match length (possibly + * longer than 'resultlen') is returned. + */ +static +int +freeze_pattern(StringInfo old, int old_info, StringSet *new_str_set, + char *pattern, int resultlen) +{ + int len; + StringInfo new; + int new_str_size; + int new_index; + + /* + * We are freezing this pattern string. If the pattern string length is + * shorter than the current longest string length, we don't need to keep + * it. + */ + if (old->len < resultlen) + return resultlen; + + if (old_info & STRSET_MATCHED) + /* we don't need to apply pattern match again */ + len = old->len; + else + { + /* apply pattern match */ + len = do_pattern_match(pattern, old->data, old->len); + if (len <= 0) + { + /* no match. we can discard it */ + return resultlen; + } + } + if (len < resultlen) + { + /* shorter match. we can discard it */ + return resultlen; + } + + /* + * Match length is the longest so far + */ + resultlen = len; /* remember the longest match */ + + /* freeze the pattern string */ + new = makeStringInfo(); + enlargeStringInfo(new, old->len + 1); + appendStringInfoString(new, old->data); + /* set frozen mark */ + string_set_add(new_str_set, new, STRSET_FROZEN); + + /* + * Search new_str_set to find out frozen entries that have shorter match + * length. Mark them as "discard" so that they are discarded in the next + * round. + */ + new_str_size = + string_set_get_size(new_str_set) - 1; + + /* loop over new_str_set */ + for (new_index = 0; new_index < new_str_size; new_index++) + { + int info; + + new = string_set_get(new_str_set, new_index, &info); + + /* + * If this is frozen and is not longer than the current longest match + * length, we don't need to keep this. + */ + if (info & STRSET_FROZEN && new->len < resultlen) + { + /* + * mark this set to discard in the next round + */ + info |= STRSET_DISCARDED; + new_str_set->info[new_index] = info; + } + } + return resultlen; +} + +/* + * do_pattern_match + * + * Perform pattern match using 'pattern' against 'encoded_str' whose length is + * 'len' bytes (without null terminate). Returns matching number of rows if + * matching is succeeded. Otherwise returns 0. + */ +static +int +do_pattern_match(char *pattern, char *encoded_str, int len) +{ + static regex_t *regcache = NULL; + static regex_t preg; + static char patbuf[1024]; /* most recent 'pattern' is cached here */ + int plen; + int cflags = REG_EXTENDED; + size_t nmatch = 1; + int eflags = 0; + regmatch_t pmatch[1]; + int sts; + pg_wchar *data; + int data_len; + + /* + * Compile regexp if cache does not exist or existing cache is not same as + * "pattern". + */ + if (strcmp(patbuf, pattern)) + { + /* + * The compiled re must live in top memory context because patbuf is + * static data. + */ + MemoryContext oldContext = MemoryContextSwitchTo(TopMemoryContext); + + if (regcache != NULL) + pg_regfree(regcache); /* free previous re */ + + /* we need to convert to char to pg_wchar */ + plen = strlen(pattern); + data = (pg_wchar *) palloc((plen + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(pattern, data, plen); + /* compile re */ + sts = pg_regcomp(&preg, /* compiled re */ + data, /* target pattern */ + data_len, /* length of pattern */ + cflags, /* compile option */ + C_COLLATION_OID /* collation */ + ); + pfree(data); + + MemoryContextSwitchTo(oldContext); + + if (sts != REG_OKAY) + { + /* re didn't compile (no need for pg_regfree, if so) */ + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("invalid regular expression: %s", pattern))); + } + + /* save cache */ + regcache = &preg; + strncpy(patbuf, pattern, sizeof(patbuf)); + } + + data = (pg_wchar *) palloc((len + 1) * sizeof(pg_wchar)); + data_len = pg_mb2wchar_with_len(encoded_str, data, len); + + /* execute the regular expression match */ + sts = pg_regexec( + &preg, /* compiled re */ + data, /* target string */ + data_len, /* length of encoded_str */ + 0, /* search start */ + NULL, /* rm details */ + nmatch, /* number of match sub re */ + pmatch, /* match result details */ + eflags); + + pfree(data); + + if (sts != REG_OKAY) + { + if (sts != REG_NOMATCH) + { + char errMsg[100]; + + pg_regerror(sts, &preg, errMsg, sizeof(errMsg)); + ereport(ERROR, + (errcode(ERRCODE_INVALID_REGULAR_EXPRESSION), + errmsg("regular expression failed: %s", errMsg))); + } + return 0; /* does not match */ + } + + len = pmatch[0].rm_eo; /* return match length */ + return len; + +} + +/* + * evaluate_pattern + * + * Evaluate expression associated with PATTERN variable vname. current_pos is + * relative row position in a frame (starting from 0). If vname is evaluated + * to true, initial letters associated with vname is appended to + * encode_str. result is out paramater representing the expression evaluation + * result is true of false. + *--------- + * Return values are: + * >=0: the last match absolute row position + * otherwise out of frame. + *--------- + */ +static +int64 +evaluate_pattern(WindowObject winobj, int64 current_pos, + char *vname, StringInfo encoded_str, bool *result) +{ + WindowAggState *winstate = winobj->winstate; + ExprContext *econtext = winstate->ss.ps.ps_ExprContext; + ListCell *lc1, + *lc2, + *lc3; + ExprState *pat; + Datum eval_result; + bool out_of_frame = false; + bool isnull; + TupleTableSlot *slot; + + forthree(lc1, winstate->defineVariableList, + lc2, winstate->defineClauseList, + lc3, winstate->defineInitial) + { + char initial; /* initial letter associated with vname */ + char *name = strVal(lfirst(lc1)); + + if (strcmp(vname, name)) + continue; + + initial = *(strVal(lfirst(lc3))); + + /* set expression to evaluate */ + pat = lfirst(lc2); + + /* get current, previous and next tuples */ + if (!get_slots(winobj, current_pos)) + { + out_of_frame = true; + } + else + { + /* evaluate the expression */ + eval_result = ExecEvalExpr(pat, econtext, &isnull); + if (isnull) + { + /* expression is NULL */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + if (!DatumGetBool(eval_result)) + { + /* expression is false */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT, + vname, current_pos); +#endif + *result = false; + } + else + { + /* expression is true */ +#ifdef RPR_DEBUG + elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT, + vname, current_pos); +#endif + appendStringInfoChar(encoded_str, initial); + *result = true; + } + } + + slot = winstate->temp_slot_1; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->prev_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + slot = winstate->next_slot; + if (slot != winstate->null_slot) + ExecClearTuple(slot); + + break; + } + + if (out_of_frame) + { + *result = false; + return -1; + } + } + return current_pos; +} + +/* + * get_slots + * + * Get current, previous and next tuples. + * Returns false if current row is out of partition/full frame. + */ +static +bool +get_slots(WindowObject winobj, int64 current_pos) +{ + WindowAggState *winstate = winobj->winstate; + TupleTableSlot *slot; + int ret; + ExprContext *econtext; + + econtext = winstate->ss.ps.ps_ExprContext; + + /* set up current row tuple slot */ + slot = winstate->temp_slot_1; + if (!window_gettupleslot(winobj, current_pos, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT, + current_pos); +#endif + return false; + } + ret = row_is_in_frame(winstate, current_pos, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT, + current_pos); +#endif + ExecClearTuple(slot); + return false; + } + econtext->ecxt_outertuple = slot; + + /* for PREV */ + if (current_pos > 0) + { + slot = winstate->prev_slot; + if (!window_gettupleslot(winobj, current_pos - 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT, + current_pos - 1); +#endif + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos - 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT, + current_pos - 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_scantuple = winstate->null_slot; + } + else + { + econtext->ecxt_scantuple = slot; + } + } + } + else + econtext->ecxt_scantuple = winstate->null_slot; + + /* for NEXT */ + slot = winstate->next_slot; + if (!window_gettupleslot(winobj, current_pos + 1, slot)) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT, + current_pos + 1); +#endif + econtext->ecxt_innertuple = winstate->null_slot; + } + else + { + ret = row_is_in_frame(winstate, current_pos + 1, slot); + if (ret <= 0) + { +#ifdef RPR_DEBUG + elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT, + current_pos + 1); +#endif + ExecClearTuple(slot); + econtext->ecxt_innertuple = winstate->null_slot; + } + else + econtext->ecxt_innertuple = slot; + } + return true; +} + +/* + * pattern_initial + * + * Return pattern variable initial character + * matching with pattern variable name vname. + * If not found, return 0. + */ +static +char +pattern_initial(WindowAggState *winstate, char *vname) +{ + char initial; + char *name; + ListCell *lc1, + *lc2; + + forboth(lc1, winstate->defineVariableList, + lc2, winstate->defineInitial) + { + name = strVal(lfirst(lc1)); /* DEFINE variable name */ + initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */ + + + if (!strcmp(name, vname)) + return initial; /* found */ + } + return 0; +} + +/* + * string_set_init + * + * Create dynamic set of StringInfo. + */ +static +StringSet * +string_set_init(void) +{ +/* Initial allocation size of str_set */ +#define STRING_SET_ALLOC_SIZE 1024 + + StringSet *string_set; + Size set_size; + + string_set = palloc0(sizeof(StringSet)); + string_set->set_index = 0; + set_size = STRING_SET_ALLOC_SIZE; + string_set->str_set = palloc(set_size * sizeof(StringInfo)); + string_set->info = palloc0(set_size * sizeof(int)); + string_set->set_size = set_size; + + return string_set; +} + +/* + * string_set_add + * + * Add StringInfo str to StringSet string_set. + */ +static +void +string_set_add(StringSet *string_set, StringInfo str, int info) +{ + Size set_size; + Size old_set_size; + + set_size = string_set->set_size; + if (string_set->set_index >= set_size) + { + old_set_size = set_size; + set_size *= 2; + string_set->str_set = repalloc(string_set->str_set, + set_size * sizeof(StringInfo)); + string_set->info = repalloc0(string_set->info, + old_set_size * sizeof(int), + set_size * sizeof(int)); + string_set->set_size = set_size; + } + + string_set->info[string_set->set_index] = info; + string_set->str_set[string_set->set_index++] = str; + + return; +} + +/* + * string_set_get + * + * Returns StringInfo specified by index. + * If there's no data yet, returns NULL. + */ +static +StringInfo +string_set_get(StringSet *string_set, int index, int *info) +{ + *info = 0; + + /* no data? */ + if (index == 0 && string_set->set_index == 0) + return NULL; + + if (index < 0 || index >= string_set->set_index) + elog(ERROR, "invalid index: %d", index); + + *info = string_set->info[index]; + + return string_set->str_set[index]; +} + +/* + * string_set_get_size + * + * Returns the size of StringSet. + */ +static +int +string_set_get_size(StringSet *string_set) +{ + return string_set->set_index; +} + +/* + * string_set_discard + * Discard StringSet. + * All memory including StringSet itself is freed. + */ +static +void +string_set_discard(StringSet *string_set) +{ + int i; + + for (i = 0; i < string_set->set_index; i++) + { + StringInfo str = string_set->str_set[i]; + + if (str) + destroyStringInfo(str); + } + pfree(string_set->info); + pfree(string_set->str_set); + pfree(string_set); +} + +/* + * variable_pos_init + * + * Create and initialize variable postion structure + */ +static +VariablePos * +variable_pos_init(void) +{ + VariablePos *variable_pos; + + variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS); + MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS); + return variable_pos; +} + +/* + * variable_pos_register + * + * Register pattern variable whose initial is initial into postion index. + * pos is position of initial. + * If pos is already registered, register it at next empty slot. + */ +static +void +variable_pos_register(VariablePos *variable_pos, char initial, int pos) +{ + int index = initial - 'a'; + int slot; + int i; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + for (i = 0; i < NUM_ALPHABETS; i++) + { + slot = variable_pos[index].pos[i]; + if (slot < 0) + { + /* empty slot found */ + variable_pos[index].pos[i] = pos; + return; + } + } + elog(ERROR, "no empty slot for initial: %c", initial); +} + +/* + * variable_pos_compare + * + * Returns true if initial1 can be followed by initial2 + */ +static +bool +variable_pos_compare(VariablePos *variable_pos, char initial1, char initial2) +{ + int index1, + index2; + int pos1, + pos2; + + for (index1 = 0;; index1++) + { + pos1 = variable_pos_fetch(variable_pos, initial1, index1); + if (pos1 < 0) + break; + + for (index2 = 0;; index2++) + { + pos2 = variable_pos_fetch(variable_pos, initial2, index2); + if (pos2 < 0) + break; + if (pos1 <= pos2) + return true; + } + } + return false; +} + +/* + * variable_pos_fetch + * + * Fetch position of pattern variable whose initial is initial, and whose index + * is index. If no postion was registered by initial, index, returns -1. + */ +static +int +variable_pos_fetch(VariablePos *variable_pos, char initial, int index) +{ + int pos = initial - 'a'; + + if (pos < 0 || pos > NUM_ALPHABETS) + elog(ERROR, "initial is not valid char: %c", initial); + + if (index < 0 || index > NUM_ALPHABETS) + elog(ERROR, "index is not valid: %d", index); + + return variable_pos[pos].pos[index]; +} + +/* + * variable_pos_build + * + * Build VariablePos structure and return it. + */ +static +VariablePos * +variable_pos_build(WindowAggState *winstate) +{ + VariablePos *variable_pos; + StringInfo pattern_str; + int initial_index = 0; + ListCell *lc1, + *lc2; + + variable_pos = winstate->variable_pos = variable_pos_init(); + pattern_str = winstate->pattern_str = makeStringInfo(); + appendStringInfoChar(pattern_str, '^'); + + forboth(lc1, winstate->patternVariableList, + lc2, winstate->patternRegexpList) + { + char *vname = strVal(lfirst(lc1)); + char *quantifier = strVal(lfirst(lc2)); + char initial; + + initial = pattern_initial(winstate, vname); + Assert(initial != 0); + appendStringInfoChar(pattern_str, initial); + if (quantifier[0]) + appendStringInfoChar(pattern_str, quantifier[0]); + + /* + * Register the initial at initial_index. If the initial appears more + * than once, all of it's initial_index will be recorded. This could + * happen if a pattern variable appears in the PATTERN clause more + * than once like "UP DOWN UP" "UP UP UP". + */ + variable_pos_register(variable_pos, initial, initial_index); + + initial_index++; + } + + return variable_pos; +} diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c index 473c61569f..3142a8bc06 100644 --- a/src/backend/utils/adt/windowfuncs.c +++ b/src/backend/utils/adt/windowfuncs.c @@ -13,6 +13,9 @@ */ #include "postgres.h" +#include "catalog/pg_collation_d.h" +#include "executor/executor.h" +#include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "nodes/supportnodes.h" #include "utils/fmgrprotos.h" @@ -37,11 +40,19 @@ typedef struct int64 remainder; /* (total rows) % (bucket num) */ } ntile_context; +/* + * rpr process information. + * Used for AFTER MATCH SKIP PAST LAST ROW + */ +typedef struct SkipContext +{ + int64 pos; /* last row absolute position */ +} SkipContext; + static bool rank_up(WindowObject winobj); static Datum leadlag_common(FunctionCallInfo fcinfo, bool forward, bool withoffset, bool withdefault); - /* * utility routine for *_rank functions. */ @@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS) bool isnull; result = WinGetFuncArgInFrame(winobj, 0, - 0, WINDOW_SEEK_TAIL, true, + 0, WINDOW_SEEK_TAIL, false, &isnull, NULL); if (isnull) PG_RETURN_NULL(); @@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS) PG_RETURN_DATUM(result); } + +/* + * prev + * Dummy function to invoke RPR's navigation operator "PREV". + * This is *not* a window function. + */ +Datum +window_prev(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} + +/* + * next + * Dummy function to invoke RPR's navigation operation "NEXT". + * This is *not* a window function. + */ +Datum +window_next(PG_FUNCTION_ARGS) +{ + PG_RETURN_DATUM(PG_GETARG_DATUM(0)); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index 2dcc2d42da..ee11ee2c8b 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -10664,6 +10664,12 @@ { oid => '3114', descr => 'fetch the Nth row value', proname => 'nth_value', prokind => 'w', prorettype => 'anyelement', proargtypes => 'anyelement int4', prosrc => 'window_nth_value' }, +{ oid => '8126', descr => 'previous value', + proname => 'prev', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_prev' }, +{ oid => '8127', descr => 'next value', + proname => 'next', provolatile => 's', prorettype => 'anyelement', + proargtypes => 'anyelement', prosrc => 'window_next' }, # functions for range types { oid => '3832', descr => 'I/O', diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index 1590b64392..f96782fd6a 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -2585,6 +2585,37 @@ typedef enum WindowAggStatus * tuples during spool */ } WindowAggStatus; +#define RF_NOT_DETERMINED 0 +#define RF_FRAME_HEAD 1 +#define RF_SKIPPED 2 +#define RF_UNMATCHED 3 + +/* + * Allowed PATTERN variables positions. + * Used in RPR. + * + * pos represents the pattern variable defined order in DEFINE caluase. For + * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP" + * will create: + * VariablePos[0].pos[0] = 0; START + * VariablePos[1].pos[0] = 1; UP + * VariablePos[1].pos[1] = 3; UP + * VariablePos[2].pos[0] = 2; DOWN + * + * Note that UP has two pos because UP appears in PATTERN twice. + * + * By using this strucrture, we can know which pattern variable can be followed + * by which pattern variable(s). For example, START can be followed by UP and + * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2. + * DOWN can be followed by UP since UP's pos is either 1 or 3. + * + */ +#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */ +typedef struct VariablePos +{ + int pos[NUM_ALPHABETS]; /* postions in PATTERN */ +} VariablePos; + typedef struct WindowAggState { ScanState ss; /* its first field is NodeTag */ @@ -2644,6 +2675,21 @@ typedef struct WindowAggState int64 groupheadpos; /* current row's peer group head position */ int64 grouptailpos; /* " " " " tail position (group end+1) */ + /* these fields are used in Row pattern recognition: */ + RPSkipTo rpSkipTo; /* Row Pattern Skip To type */ + List *patternVariableList; /* list of row pattern variables names + * (list of String) */ + List *patternRegexpList; /* list of row pattern regular expressions + * ('+' or ''. list of String) */ + List *defineVariableList; /* list of row pattern definition + * variables (list of String) */ + List *defineClauseList; /* expression for row pattern definition + * search conditions ExprState list */ + List *defineInitial; /* list of row pattern definition variable + * initials (list of String) */ + VariablePos *variable_pos; /* list of pattern variable positions */ + StringInfo pattern_str; /* PATTERN initials */ + MemoryContext partcontext; /* context for partition-lifespan data */ MemoryContext aggcontext; /* shared context for aggregate working data */ MemoryContext curaggcontext; /* current aggregate's working data */ @@ -2671,6 +2717,18 @@ typedef struct WindowAggState TupleTableSlot *agg_row_slot; TupleTableSlot *temp_slot_1; TupleTableSlot *temp_slot_2; + + /* temporary slots for RPR */ + TupleTableSlot *prev_slot; /* PREV row navigation operator */ + TupleTableSlot *next_slot; /* NEXT row navigation operator */ + TupleTableSlot *null_slot; /* all NULL slot */ + + /* + * Each byte corresponds to a row positioned at absolute its pos in + * partition. See above definition for RF_* + */ + char *reduced_frame_map; + int64 alloc_sz; /* size of the map */ } WindowAggState; /* ---------------- -- 2.25.1 ----Next_Part(Tue_Dec_31_08_57_07_2024_963)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v27-0006-Row-pattern-recognition-patch-docs.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
* [PATCH 2/3] replace CppAsString2(RELKIND_x) with RELKIND_x_STR @ 2026-02-01 23:45 Álvaro Herrera <[email protected]> 0 siblings, 0 replies; 128+ messages in thread From: Álvaro Herrera @ 2026-02-01 23:45 UTC (permalink / raw) --- contrib/oid2name/oid2name.c | 18 +++--- contrib/postgres_fdw/postgres_fdw.c | 10 +-- contrib/vacuumlo/vacuumlo.c | 2 +- src/backend/commands/subscriptioncmds.c | 4 +- src/backend/utils/adt/xml.c | 12 ++-- src/bin/initdb/initdb.c | 20 +++--- src/bin/pg_amcheck/pg_amcheck.c | 32 ++++----- src/bin/pg_dump/pg_dump.c | 36 +++++------ src/bin/pg_upgrade/check.c | 6 +- src/bin/pg_upgrade/info.c | 6 +- src/bin/pg_upgrade/pg_upgrade.c | 12 ++-- src/bin/psql/describe.c | 74 ++++++++++----------- src/bin/psql/tab-complete.in.c | 86 ++++++++++++------------- src/bin/scripts/reindexdb.c | 8 +-- src/bin/scripts/vacuuming.c | 14 ++-- 15 files changed, 170 insertions(+), 170 deletions(-) diff --git a/contrib/oid2name/oid2name.c b/contrib/oid2name/oid2name.c index 51802907138..463bdfae320 100644 --- a/contrib/oid2name/oid2name.c +++ b/contrib/oid2name/oid2name.c @@ -477,8 +477,8 @@ sql_exec_dumpalltables(PGconn *conn, struct options *opts) " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace " " LEFT JOIN pg_catalog.pg_database d ON d.datname = pg_catalog.current_database()," " pg_catalog.pg_tablespace t " - "WHERE relkind IN (" CppAsString2(RELKIND_RELATION) "," - CppAsString2(RELKIND_MATVIEW) "%s%s) AND " + "WHERE relkind IN (" RELKIND_RELATION_STR "," + RELKIND_MATVIEW_STR "%s%s) AND " " %s" " t.oid = CASE" " WHEN reltablespace <> 0 THEN reltablespace" @@ -486,8 +486,8 @@ sql_exec_dumpalltables(PGconn *conn, struct options *opts) " END " "ORDER BY relname", opts->extended ? addfields : "", - opts->indexes ? "," CppAsString2(RELKIND_INDEX) "," CppAsString2(RELKIND_SEQUENCE) : "", - opts->systables ? "," CppAsString2(RELKIND_TOASTVALUE) : "", + opts->indexes ? "," RELKIND_INDEX_STR "," RELKIND_SEQUENCE_STR : "", + opts->systables ? "," RELKIND_TOASTVALUE_STR : "", opts->systables ? "" : "n.nspname NOT IN ('pg_catalog', 'information_schema') AND n.nspname !~ '^pg_toast' AND"); sql_exec(conn, todo, opts->quiet); @@ -548,11 +548,11 @@ sql_exec_searchtables(PGconn *conn, struct options *opts) " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n" " LEFT JOIN pg_catalog.pg_database d ON d.datname = pg_catalog.current_database(),\n" " pg_catalog.pg_tablespace t\n" - "WHERE relkind IN (" CppAsString2(RELKIND_RELATION) "," - CppAsString2(RELKIND_MATVIEW) "," - CppAsString2(RELKIND_INDEX) "," - CppAsString2(RELKIND_SEQUENCE) "," - CppAsString2(RELKIND_TOASTVALUE) ") AND\n" + "WHERE relkind IN (" RELKIND_RELATION_STR "," + RELKIND_MATVIEW_STR "," + RELKIND_INDEX_STR "," + RELKIND_SEQUENCE_STR "," + RELKIND_TOASTVALUE_STR ") AND\n" " t.oid = CASE\n" " WHEN reltablespace <> 0 THEN reltablespace\n" " ELSE dattablespace\n" diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 3572689e33b..e0457bb1253 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -5496,11 +5496,11 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid) appendStringInfoString(&buf, "WHERE c.relkind IN (" - CppAsString2(RELKIND_RELATION) "," - CppAsString2(RELKIND_VIEW) "," - CppAsString2(RELKIND_FOREIGN_TABLE) "," - CppAsString2(RELKIND_MATVIEW) "," - CppAsString2(RELKIND_PARTITIONED_TABLE) ") " + RELKIND_RELATION_STR "," + RELKIND_VIEW_STR "," + RELKIND_FOREIGN_TABLE_STR "," + RELKIND_MATVIEW_STR "," + RELKIND_PARTITIONED_TABLE_STR ") " " AND n.nspname = "); deparseStringLiteral(&buf, stmt->remote_schema); diff --git a/contrib/vacuumlo/vacuumlo.c b/contrib/vacuumlo/vacuumlo.c index 8102569466b..343dae9bc20 100644 --- a/contrib/vacuumlo/vacuumlo.c +++ b/contrib/vacuumlo/vacuumlo.c @@ -198,7 +198,7 @@ vacuumlo(const char *database, const struct _param *param) strcat(buf, " AND a.atttypid = t.oid "); strcat(buf, " AND c.relnamespace = s.oid "); strcat(buf, " AND t.typname in ('oid', 'lo') "); - strcat(buf, " AND c.relkind in (" CppAsString2(RELKIND_RELATION) ", " CppAsString2(RELKIND_MATVIEW) ")"); + strcat(buf, " AND c.relkind in ('" RELKIND_RELATION_STR "', " RELKIND_MATVIEW_STR ")"); strcat(buf, " AND s.nspname !~ '^pg_'"); res = PQexec(conn, buf); if (PQresultStatus(res) != PGRES_TUPLES_OK) diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c index 0b3c8499b49..33e3c25a50c 100644 --- a/src/backend/commands/subscriptioncmds.c +++ b/src/backend/commands/subscriptioncmds.c @@ -2921,7 +2921,7 @@ fetch_relation_list(WalReceiverConn *wrconn, List *publications) if (server_version >= 190000) appendStringInfo(&cmd, "UNION ALL\n" - " SELECT DISTINCT s.schemaname, s.sequencename, " CppAsString2(RELKIND_SEQUENCE) "::\"char\" AS relkind, NULL::int2vector AS attrs\n" + " SELECT DISTINCT s.schemaname, s.sequencename, " RELKIND_SEQUENCE_STR "::\"char\" AS relkind, NULL::int2vector AS attrs\n" " FROM pg_catalog.pg_publication_sequences s\n" " WHERE s.pubname IN ( %s )", pub_names.data); @@ -2929,7 +2929,7 @@ fetch_relation_list(WalReceiverConn *wrconn, List *publications) else { tableRow[3] = NAMEARRAYOID; - appendStringInfoString(&cmd, "SELECT DISTINCT t.schemaname, t.tablename, " CppAsString2(RELKIND_RELATION) "::\"char\" AS relkind \n"); + appendStringInfoString(&cmd, "SELECT DISTINCT t.schemaname, t.tablename, " RELKIND_RELATION_STR "::\"char\" AS relkind \n"); /* Get column lists for each relation if the publisher supports it */ if (check_columnlist) diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c index f69dc68286c..7de019a7402 100644 --- a/src/backend/utils/adt/xml.c +++ b/src/backend/utils/adt/xml.c @@ -2857,9 +2857,9 @@ schema_get_xml_visible_tables(Oid nspid) initStringInfo(&query); appendStringInfo(&query, "SELECT oid FROM pg_catalog.pg_class" " WHERE relnamespace = %u AND relkind IN (" - CppAsString2(RELKIND_RELATION) "," - CppAsString2(RELKIND_MATVIEW) "," - CppAsString2(RELKIND_VIEW) ")" + RELKIND_RELATION_STR "," + RELKIND_MATVIEW_STR "," + RELKIND_VIEW_STR ")" " AND pg_catalog.has_table_privilege (oid, 'SELECT')" " ORDER BY relname;", nspid); @@ -2889,9 +2889,9 @@ database_get_xml_visible_tables(void) /* At the moment there is no order required here. */ return query_to_oid_list("SELECT oid FROM pg_catalog.pg_class" " WHERE relkind IN (" - CppAsString2(RELKIND_RELATION) "," - CppAsString2(RELKIND_MATVIEW) "," - CppAsString2(RELKIND_VIEW) ")" + RELKIND_RELATION_STR "," + RELKIND_MATVIEW_STR "," + RELKIND_VIEW_STR ")" " AND pg_catalog.has_table_privilege(pg_class.oid, 'SELECT')" " AND relnamespace IN (" XML_VISIBLE_SCHEMAS ");"); } diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c index a3980e5535f..11bfdd31cbf 100644 --- a/src/bin/initdb/initdb.c +++ b/src/bin/initdb/initdb.c @@ -1806,12 +1806,12 @@ setup_privileges(FILE *cmdfd) " SET relacl = (SELECT array_agg(a.acl) FROM " " (SELECT E'=r/\"%s\"' as acl " " UNION SELECT unnest(pg_catalog.acldefault(" - " CASE WHEN relkind = " CppAsString2(RELKIND_SEQUENCE) " THEN 's' " + " CASE WHEN relkind = " RELKIND_SEQUENCE_STR " THEN 's' " " ELSE 'r' END::\"char\"," CppAsString2(BOOTSTRAP_SUPERUSERID) "::oid))" " ) as a) " - " WHERE relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_VIEW) ", " CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_SEQUENCE) ")" + " WHERE relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_VIEW_STR ", " RELKIND_MATVIEW_STR ", " + RELKIND_SEQUENCE_STR ")" " AND relacl IS NULL;\n\n", escape_quotes(username)); PG_CMD_PUTS("GRANT USAGE ON SCHEMA pg_catalog, public TO PUBLIC;\n\n"); @@ -1828,9 +1828,9 @@ setup_privileges(FILE *cmdfd) " pg_class" " WHERE" " relacl IS NOT NULL" - " AND relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_VIEW) ", " CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_SEQUENCE) ");\n\n"); + " AND relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_VIEW_STR ", " RELKIND_MATVIEW_STR ", " + RELKIND_SEQUENCE_STR ");\n\n"); PG_CMD_PUTS("INSERT INTO pg_init_privs " " (objoid, classoid, objsubid, initprivs, privtype)" " SELECT" @@ -1844,9 +1844,9 @@ setup_privileges(FILE *cmdfd) " JOIN pg_attribute ON (pg_class.oid = pg_attribute.attrelid)" " WHERE" " pg_attribute.attacl IS NOT NULL" - " AND pg_class.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_VIEW) ", " CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_SEQUENCE) ");\n\n"); + " AND pg_class.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_VIEW_STR ", " RELKIND_MATVIEW_STR ", " + RELKIND_SEQUENCE_STR ");\n\n"); PG_CMD_PUTS("INSERT INTO pg_init_privs " " (objoid, classoid, objsubid, initprivs, privtype)" " SELECT" diff --git a/src/bin/pg_amcheck/pg_amcheck.c b/src/bin/pg_amcheck/pg_amcheck.c index 03e24a2577c..72bfcd2c813 100644 --- a/src/bin/pg_amcheck/pg_amcheck.c +++ b/src/bin/pg_amcheck/pg_amcheck.c @@ -1976,28 +1976,28 @@ compile_relation_list_one_db(PGconn *conn, SimplePtrList *relations, appendPQExpBuffer(&sql, " AND c.relam = %u " "AND c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_SEQUENCE) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_TOASTVALUE) ") " + RELKIND_RELATION_STR ", " + RELKIND_SEQUENCE_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_TOASTVALUE_STR ") " "AND c.relnamespace != %u", HEAP_TABLE_AM_OID, PG_TOAST_NAMESPACE); else appendPQExpBuffer(&sql, " AND c.relam IN (%u, %u)" "AND c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_SEQUENCE) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_TOASTVALUE) ", " - CppAsString2(RELKIND_INDEX) ") " + RELKIND_RELATION_STR ", " + RELKIND_SEQUENCE_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_TOASTVALUE_STR ", " + RELKIND_INDEX_STR ") " "AND ((c.relam = %u AND c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_SEQUENCE) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_TOASTVALUE) ")) OR " + RELKIND_RELATION_STR ", " + RELKIND_SEQUENCE_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_TOASTVALUE_STR ")) OR " "(c.relam = %u AND c.relkind = " - CppAsString2(RELKIND_INDEX) "))", + RELKIND_INDEX_STR "))", HEAP_TABLE_AM_OID, BTREE_AM_OID, HEAP_TABLE_AM_OID, BTREE_AM_OID); @@ -2058,7 +2058,7 @@ compile_relation_list_one_db(PGconn *conn, SimplePtrList *relations, "\nWHERE true"); appendPQExpBuffer(&sql, " AND c.relam = %u " - "AND c.relkind = " CppAsString2(RELKIND_INDEX), + "AND c.relkind = " RELKIND_INDEX_STR, BTREE_AM_OID); if (opts.no_toast_expansion) appendPQExpBuffer(&sql, @@ -2095,7 +2095,7 @@ compile_relation_list_one_db(PGconn *conn, SimplePtrList *relations, "\nWHERE true"); appendPQExpBuffer(&sql, " AND c.relam = %u" - " AND c.relkind = " CppAsString2(RELKIND_INDEX) ")", + " AND c.relkind = " RELKIND_INDEX_STR ")", BTREE_AM_OID); } diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c index 2bebefd0ba2..cdccccc1820 100644 --- a/src/bin/pg_dump/pg_dump.c +++ b/src/bin/pg_dump/pg_dump.c @@ -3158,14 +3158,14 @@ buildMatViewRefreshDependencies(Archive *fout) "SELECT d1.objid, d2.refobjid, c2.relkind AS refrelkind " "FROM pg_depend d1 " "JOIN pg_class c1 ON c1.oid = d1.objid " - "AND c1.relkind = " CppAsString2(RELKIND_MATVIEW) + "AND c1.relkind = " RELKIND_MATVIEW_STR " JOIN pg_rewrite r1 ON r1.ev_class = d1.objid " "JOIN pg_depend d2 ON d2.classid = 'pg_rewrite'::regclass " "AND d2.objid = r1.oid " "AND d2.refobjid <> d1.objid " "JOIN pg_class c2 ON c2.oid = d2.refobjid " - "AND c2.relkind IN (" CppAsString2(RELKIND_MATVIEW) "," - CppAsString2(RELKIND_VIEW) ") " + "AND c2.relkind IN (" RELKIND_MATVIEW_STR "," + RELKIND_VIEW_STR ") " "WHERE d1.classid = 'pg_class'::regclass " "UNION " "SELECT w.objid, d3.refobjid, c3.relkind " @@ -3175,12 +3175,12 @@ buildMatViewRefreshDependencies(Archive *fout) "AND d3.objid = r3.oid " "AND d3.refobjid <> w.refobjid " "JOIN pg_class c3 ON c3.oid = d3.refobjid " - "AND c3.relkind IN (" CppAsString2(RELKIND_MATVIEW) "," - CppAsString2(RELKIND_VIEW) ") " + "AND c3.relkind IN (" RELKIND_MATVIEW_STR "," + RELKIND_VIEW_STR ") " ") " "SELECT 'pg_class'::regclass::oid AS classid, objid, refobjid " "FROM w " - "WHERE refrelkind = " CppAsString2(RELKIND_MATVIEW)); + "WHERE refrelkind = " RELKIND_MATVIEW_STR); res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK); @@ -7279,9 +7279,9 @@ getTables(Archive *fout, int *numTables) "c.relhastriggers, c.relpersistence, " "c.reloftype, " "c.relacl, " - "acldefault(CASE WHEN c.relkind = " CppAsString2(RELKIND_SEQUENCE) + "acldefault(CASE WHEN c.relkind = " RELKIND_SEQUENCE_STR " THEN 's'::\"char\" ELSE 'r'::\"char\" END, c.relowner) AS acldefault, " - "CASE WHEN c.relkind = " CppAsString2(RELKIND_FOREIGN_TABLE) " THEN " + "CASE WHEN c.relkind = " RELKIND_FOREIGN_TABLE_STR " THEN " "(SELECT ftserver FROM pg_catalog.pg_foreign_table WHERE ftrelid = c.oid) " "ELSE 0 END AS foreignserver, " "c.relfrozenxid, tc.relfrozenxid AS tfrozenxid, " @@ -7367,7 +7367,7 @@ getTables(Archive *fout, int *numTables) appendPQExpBufferStr(query, "\nFROM pg_class c\n" "LEFT JOIN pg_depend d ON " - "(c.relkind = " CppAsString2(RELKIND_SEQUENCE) " AND " + "(c.relkind = " RELKIND_SEQUENCE_STR " AND " "d.classid = 'pg_class'::regclass AND d.objid = c.oid AND " "d.objsubid = 0 AND " "d.refclassid = 'pg_class'::regclass AND d.deptype IN ('a', 'i'))\n" @@ -7387,8 +7387,8 @@ getTables(Archive *fout, int *numTables) */ appendPQExpBufferStr(query, "LEFT JOIN pg_class tc ON (c.reltoastrelid = tc.oid" - " AND tc.relkind = " CppAsString2(RELKIND_TOASTVALUE) - " AND c.relkind <> " CppAsString2(RELKIND_PARTITIONED_TABLE) ")\n"); + " AND tc.relkind = " RELKIND_TOASTVALUE_STR + " AND c.relkind <> " RELKIND_PARTITIONED_TABLE_STR ")\n"); /* * Restrict to interesting relkinds (in particular, not indexes). Not all @@ -7402,13 +7402,13 @@ getTables(Archive *fout, int *numTables) */ appendPQExpBufferStr(query, "WHERE c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_SEQUENCE) ", " - CppAsString2(RELKIND_VIEW) ", " - CppAsString2(RELKIND_COMPOSITE_TYPE) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_FOREIGN_TABLE) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ")\n" + RELKIND_RELATION_STR ", " + RELKIND_SEQUENCE_STR ", " + RELKIND_VIEW_STR ", " + RELKIND_COMPOSITE_TYPE_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_FOREIGN_TABLE_STR ", " + RELKIND_PARTITIONED_TABLE_STR ")\n" "ORDER BY c.oid"); res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK); diff --git a/src/bin/pg_upgrade/check.c b/src/bin/pg_upgrade/check.c index a8d20a92a98..5d053563657 100644 --- a/src/bin/pg_upgrade/check.c +++ b/src/bin/pg_upgrade/check.c @@ -372,9 +372,9 @@ data_type_check_query(int checknum) " NOT a.attisdropped AND " " a.atttypid IN (SELECT oid FROM oids) AND " " c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_INDEX) ") AND " + RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_INDEX_STR ") AND " " c.relnamespace = n.oid AND " /* exclude possible orphaned temp tables */ " n.nspname !~ '^pg_temp_' AND " diff --git a/src/bin/pg_upgrade/info.c b/src/bin/pg_upgrade/info.c index 47e8d1039a2..89bda44fcf9 100644 --- a/src/bin/pg_upgrade/info.c +++ b/src/bin/pg_upgrade/info.c @@ -508,8 +508,8 @@ get_rel_infos_query(void) " SELECT c.oid, 0::oid, 0::oid " " FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n " " ON c.relnamespace = n.oid " - " WHERE relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) "%s) AND " + " WHERE relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR "%s) AND " /* exclude possible orphaned temp tables */ " ((n.nspname !~ '^pg_temp_' AND " " n.nspname !~ '^pg_toast_temp_' AND " @@ -519,7 +519,7 @@ get_rel_infos_query(void) " (n.nspname = 'pg_catalog' AND " " relname IN ('pg_largeobject'%s) ))), ", (user_opts.transfer_mode == TRANSFER_MODE_SWAP) ? - ", " CppAsString2(RELKIND_SEQUENCE) : "", + ", " RELKIND_SEQUENCE_STR : "", FirstNormalObjectId, (GET_MAJOR_VERSION(old_cluster.major_version) >= 1600) ? ", 'pg_largeobject_metadata'" : ""); diff --git a/src/bin/pg_upgrade/pg_upgrade.c b/src/bin/pg_upgrade/pg_upgrade.c index 2127d297bfe..e94f02fd369 100644 --- a/src/bin/pg_upgrade/pg_upgrade.c +++ b/src/bin/pg_upgrade/pg_upgrade.c @@ -990,9 +990,9 @@ set_frozenxids(bool minmxid_only) "SET relfrozenxid = '%u' " /* only heap, materialized view, and TOAST are vacuumed */ "WHERE relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_TOASTVALUE) ")", + RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_TOASTVALUE_STR ")", old_cluster.controldata.chkpnt_nxtxid)); /* set pg_class.relminmxid */ @@ -1001,9 +1001,9 @@ set_frozenxids(bool minmxid_only) "SET relminmxid = '%u' " /* only heap, materialized view, and TOAST are vacuumed */ "WHERE relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_TOASTVALUE) ")", + RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_TOASTVALUE_STR ")", old_cluster.controldata.chkpnt_nxtmulti)); PQfinish(conn); diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c index 3584c4e1428..f02a8df8875 100644 --- a/src/bin/psql/describe.c +++ b/src/bin/psql/describe.c @@ -689,7 +689,7 @@ describeTypes(const char *pattern, bool verbose, bool showSystem) * composite types */ appendPQExpBufferStr(&buf, "WHERE (t.typrelid = 0 "); - appendPQExpBufferStr(&buf, "OR (SELECT c.relkind = " CppAsString2(RELKIND_COMPOSITE_TYPE) + appendPQExpBufferStr(&buf, "OR (SELECT c.relkind = " RELKIND_COMPOSITE_TYPE_STR " FROM pg_catalog.pg_class c " "WHERE c.oid = t.typrelid))\n"); @@ -1063,12 +1063,12 @@ permissionsList(const char *pattern, bool showSystem) "SELECT n.nspname as \"%s\",\n" " c.relname as \"%s\",\n" " CASE c.relkind" - " WHEN " CppAsString2(RELKIND_RELATION) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_VIEW) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_MATVIEW) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_SEQUENCE) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_FOREIGN_TABLE) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_PARTITIONED_TABLE) " THEN '%s'" + " WHEN " RELKIND_RELATION_STR " THEN '%s'" + " WHEN " RELKIND_VIEW_STR " THEN '%s'" + " WHEN " RELKIND_MATVIEW_STR " THEN '%s'" + " WHEN " RELKIND_SEQUENCE_STR " THEN '%s'" + " WHEN " RELKIND_FOREIGN_TABLE_STR " THEN '%s'" + " WHEN " RELKIND_PARTITIONED_TABLE_STR " THEN '%s'" " END as \"%s\",\n" " ", gettext_noop("Schema"), @@ -1164,12 +1164,12 @@ permissionsList(const char *pattern, bool showSystem) appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_class c\n" " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n" "WHERE c.relkind IN (" - CppAsString2(RELKIND_RELATION) "," - CppAsString2(RELKIND_VIEW) "," - CppAsString2(RELKIND_MATVIEW) "," - CppAsString2(RELKIND_SEQUENCE) "," - CppAsString2(RELKIND_FOREIGN_TABLE) "," - CppAsString2(RELKIND_PARTITIONED_TABLE) ")\n"); + RELKIND_RELATION_STR "," + RELKIND_VIEW_STR "," + RELKIND_MATVIEW_STR "," + RELKIND_SEQUENCE_STR "," + RELKIND_FOREIGN_TABLE_STR "," + RELKIND_PARTITIONED_TABLE_STR ")\n"); if (!showSystem && !pattern) appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" @@ -3471,8 +3471,8 @@ describeOneTableDetails(const char *schemaname, "SELECT c.oid::pg_catalog.regclass\n" "FROM pg_catalog.pg_class c, pg_catalog.pg_inherits i\n" "WHERE c.oid = i.inhparent AND i.inhrelid = '%s'\n" - " AND c.relkind != " CppAsString2(RELKIND_PARTITIONED_TABLE) - " AND c.relkind != " CppAsString2(RELKIND_PARTITIONED_INDEX) + " AND c.relkind != " RELKIND_PARTITIONED_TABLE_STR + " AND c.relkind != " RELKIND_PARTITIONED_INDEX_STR "\nORDER BY inhseqno;", oid); @@ -4067,15 +4067,15 @@ listTables(const char *tabtypes, const char *pattern, bool verbose, bool showSys "SELECT n.nspname as \"%s\",\n" " c.relname as \"%s\",\n" " CASE c.relkind" - " WHEN " CppAsString2(RELKIND_RELATION) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_VIEW) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_MATVIEW) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_INDEX) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_SEQUENCE) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_TOASTVALUE) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_FOREIGN_TABLE) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_PARTITIONED_TABLE) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_PARTITIONED_INDEX) " THEN '%s'" + " WHEN " RELKIND_RELATION_STR " THEN '%s'" + " WHEN " RELKIND_VIEW_STR " THEN '%s'" + " WHEN " RELKIND_MATVIEW_STR " THEN '%s'" + " WHEN " RELKIND_INDEX_STR " THEN '%s'" + " WHEN " RELKIND_SEQUENCE_STR " THEN '%s'" + " WHEN " RELKIND_TOASTVALUE_STR " THEN '%s'" + " WHEN " RELKIND_FOREIGN_TABLE_STR " THEN '%s'" + " WHEN " RELKIND_PARTITIONED_TABLE_STR " THEN '%s'" + " WHEN " RELKIND_PARTITIONED_INDEX_STR " THEN '%s'" " END as \"%s\",\n" " pg_catalog.pg_get_userbyid(c.relowner) as \"%s\"", gettext_noop("Schema"), @@ -4157,25 +4157,25 @@ listTables(const char *tabtypes, const char *pattern, bool verbose, bool showSys appendPQExpBufferStr(&buf, "\nWHERE c.relkind IN ("); if (showTables) { - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_RELATION) "," - CppAsString2(RELKIND_PARTITIONED_TABLE) ","); + appendPQExpBufferStr(&buf, RELKIND_RELATION_STR "," + RELKIND_PARTITIONED_TABLE_STR ","); /* with 'S' or a pattern, allow 't' to match TOAST tables too */ if (showSystem || pattern) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_TOASTVALUE) ","); + appendPQExpBufferStr(&buf, RELKIND_TOASTVALUE_STR ","); } if (showViews) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_VIEW) ","); + appendPQExpBufferStr(&buf, RELKIND_VIEW_STR ","); if (showMatViews) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_MATVIEW) ","); + appendPQExpBufferStr(&buf, RELKIND_MATVIEW_STR ","); if (showIndexes) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_INDEX) "," - CppAsString2(RELKIND_PARTITIONED_INDEX) ","); + appendPQExpBufferStr(&buf, RELKIND_INDEX_STR "," + RELKIND_PARTITIONED_INDEX_STR ","); if (showSeq) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_SEQUENCE) ","); + appendPQExpBufferStr(&buf, RELKIND_SEQUENCE_STR ","); if (showSystem || pattern) appendPQExpBufferStr(&buf, "'s',"); /* was RELKIND_SPECIAL */ if (showForeign) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_FOREIGN_TABLE) ","); + appendPQExpBufferStr(&buf, RELKIND_FOREIGN_TABLE_STR ","); appendPQExpBufferStr(&buf, "''"); /* dummy */ appendPQExpBufferStr(&buf, ")\n"); @@ -4348,8 +4348,8 @@ listPartitionedTables(const char *reltypes, const char *pattern, bool verbose) { appendPQExpBuffer(&buf, ",\n CASE c.relkind" - " WHEN " CppAsString2(RELKIND_PARTITIONED_TABLE) " THEN '%s'" - " WHEN " CppAsString2(RELKIND_PARTITIONED_INDEX) " THEN '%s'" + " WHEN " RELKIND_PARTITIONED_TABLE_STR " THEN '%s'" + " WHEN " RELKIND_PARTITIONED_INDEX_STR " THEN '%s'" " END as \"%s\"", gettext_noop("partitioned table"), gettext_noop("partitioned index"), @@ -4449,9 +4449,9 @@ listPartitionedTables(const char *reltypes, const char *pattern, bool verbose) appendPQExpBufferStr(&buf, "\nWHERE c.relkind IN ("); if (showTables) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_PARTITIONED_TABLE) ","); + appendPQExpBufferStr(&buf, RELKIND_PARTITIONED_TABLE_STR ","); if (showIndexes) - appendPQExpBufferStr(&buf, CppAsString2(RELKIND_PARTITIONED_INDEX) ","); + appendPQExpBufferStr(&buf, RELKIND_PARTITIONED_INDEX_STR ","); appendPQExpBufferStr(&buf, "''"); /* dummy */ appendPQExpBufferStr(&buf, ")\n"); diff --git a/src/bin/psql/tab-complete.in.c b/src/bin/psql/tab-complete.in.c index 8b91bc00062..5434a1273b2 100644 --- a/src/bin/psql/tab-complete.in.c +++ b/src/bin/psql/tab-complete.in.c @@ -146,7 +146,7 @@ typedef struct SchemaQuery * Selection condition --- only rows meeting this condition are candidates * to display. If catname mentions multiple tables, include the necessary * join condition here. For example, this might look like "c.relkind = " - * CppAsString2(RELKIND_RELATION). Write NULL (not an empty string) if + * RELKIND_RELATION_STR. Write NULL (not an empty string) if * not needed. */ const char *selcondition; @@ -591,7 +591,7 @@ static const SchemaQuery Query_for_list_of_datatypes = { .catname = "pg_catalog.pg_type t", /* selcondition --- ignore table rowtypes and array types */ .selcondition = "(t.typrelid = 0 " - " OR (SELECT c.relkind = " CppAsString2(RELKIND_COMPOSITE_TYPE) + " OR (SELECT c.relkind = " RELKIND_COMPOSITE_TYPE_STR " FROM pg_catalog.pg_class c WHERE c.oid = t.typrelid)) " "AND t.typname !~ '^_'", .viscondition = "pg_catalog.pg_type_is_visible(t.oid)", @@ -603,7 +603,7 @@ static const SchemaQuery Query_for_list_of_datatypes = { static const SchemaQuery Query_for_list_of_composite_datatypes = { .catname = "pg_catalog.pg_type t", /* selcondition --- only get composite types */ - .selcondition = "(SELECT c.relkind = " CppAsString2(RELKIND_COMPOSITE_TYPE) + .selcondition = "(SELECT c.relkind = " RELKIND_COMPOSITE_TYPE_STR " FROM pg_catalog.pg_class c WHERE c.oid = t.typrelid) " "AND t.typname !~ '^_'", .viscondition = "pg_catalog.pg_type_is_visible(t.oid)", @@ -679,7 +679,7 @@ static const SchemaQuery Query_for_list_of_routines = { static const SchemaQuery Query_for_list_of_sequences = { .catname = "pg_catalog.pg_class c", - .selcondition = "c.relkind IN (" CppAsString2(RELKIND_SEQUENCE) ")", + .selcondition = "c.relkind IN (" RELKIND_SEQUENCE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -687,7 +687,7 @@ static const SchemaQuery Query_for_list_of_sequences = { static const SchemaQuery Query_for_list_of_foreign_tables = { .catname = "pg_catalog.pg_class c", - .selcondition = "c.relkind IN (" CppAsString2(RELKIND_FOREIGN_TABLE) ")", + .selcondition = "c.relkind IN (" RELKIND_FOREIGN_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -696,8 +696,8 @@ static const SchemaQuery Query_for_list_of_foreign_tables = { static const SchemaQuery Query_for_list_of_tables = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ")", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_PARTITIONED_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -705,7 +705,7 @@ static const SchemaQuery Query_for_list_of_tables = { static const SchemaQuery Query_for_list_of_partitioned_tables = { .catname = "pg_catalog.pg_class c", - .selcondition = "c.relkind IN (" CppAsString2(RELKIND_PARTITIONED_TABLE) ")", + .selcondition = "c.relkind IN (" RELKIND_PARTITIONED_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -714,8 +714,8 @@ static const SchemaQuery Query_for_list_of_partitioned_tables = { static const SchemaQuery Query_for_list_of_tables_for_constraint = { .catname = "pg_catalog.pg_class c, pg_catalog.pg_constraint con", .selcondition = "c.oid=con.conrelid and c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ")", + RELKIND_RELATION_STR ", " + RELKIND_PARTITIONED_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -783,7 +783,7 @@ static const SchemaQuery Query_for_list_of_ts_templates = { static const SchemaQuery Query_for_list_of_views = { .catname = "pg_catalog.pg_class c", - .selcondition = "c.relkind IN (" CppAsString2(RELKIND_VIEW) ")", + .selcondition = "c.relkind IN (" RELKIND_VIEW_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -791,7 +791,7 @@ static const SchemaQuery Query_for_list_of_views = { static const SchemaQuery Query_for_list_of_matviews = { .catname = "pg_catalog.pg_class c", - .selcondition = "c.relkind IN (" CppAsString2(RELKIND_MATVIEW) ")", + .selcondition = "c.relkind IN (" RELKIND_MATVIEW_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -800,8 +800,8 @@ static const SchemaQuery Query_for_list_of_matviews = { static const SchemaQuery Query_for_list_of_indexes = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_INDEX) ", " - CppAsString2(RELKIND_PARTITIONED_INDEX) ")", + "c.relkind IN (" RELKIND_INDEX_STR ", " + RELKIND_PARTITIONED_INDEX_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -809,7 +809,7 @@ static const SchemaQuery Query_for_list_of_indexes = { static const SchemaQuery Query_for_list_of_partitioned_indexes = { .catname = "pg_catalog.pg_class c", - .selcondition = "c.relkind = " CppAsString2(RELKIND_PARTITIONED_INDEX), + .selcondition = "c.relkind = " RELKIND_PARTITIONED_INDEX_STR, .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -827,8 +827,8 @@ static const SchemaQuery Query_for_list_of_relations = { /* partitioned relations */ static const SchemaQuery Query_for_list_of_partitioned_relations = { .catname = "pg_catalog.pg_class c", - .selcondition = "c.relkind IN (" CppAsString2(RELKIND_PARTITIONED_TABLE) - ", " CppAsString2(RELKIND_PARTITIONED_INDEX) ")", + .selcondition = "c.relkind IN (" RELKIND_PARTITIONED_TABLE_STR + ", " RELKIND_PARTITIONED_INDEX_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -845,10 +845,10 @@ static const SchemaQuery Query_for_list_of_operator_families = { static const SchemaQuery Query_for_list_of_updatables = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_FOREIGN_TABLE) ", " - CppAsString2(RELKIND_VIEW) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ")", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_FOREIGN_TABLE_STR ", " + RELKIND_VIEW_STR ", " + RELKIND_PARTITIONED_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -858,9 +858,9 @@ static const SchemaQuery Query_for_list_of_updatables = { static const SchemaQuery Query_for_list_of_mergetargets = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_VIEW) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ") ", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_VIEW_STR ", " + RELKIND_PARTITIONED_TABLE_STR ") ", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -870,12 +870,12 @@ static const SchemaQuery Query_for_list_of_mergetargets = { static const SchemaQuery Query_for_list_of_selectables = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_SEQUENCE) ", " - CppAsString2(RELKIND_VIEW) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_FOREIGN_TABLE) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ")", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_SEQUENCE_STR ", " + RELKIND_VIEW_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_FOREIGN_TABLE_STR ", " + RELKIND_PARTITIONED_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -885,9 +885,9 @@ static const SchemaQuery Query_for_list_of_selectables = { static const SchemaQuery Query_for_list_of_truncatables = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_FOREIGN_TABLE) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ")", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_FOREIGN_TABLE_STR ", " + RELKIND_PARTITIONED_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -900,10 +900,10 @@ static const SchemaQuery Query_for_list_of_truncatables = { static const SchemaQuery Query_for_list_of_analyzables = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_FOREIGN_TABLE) ")", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_PARTITIONED_TABLE_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_FOREIGN_TABLE_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -921,9 +921,9 @@ static const SchemaQuery Query_for_list_of_analyzables = { static const SchemaQuery Query_for_list_of_indexables = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ", " - CppAsString2(RELKIND_MATVIEW) ")", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_PARTITIONED_TABLE_STR ", " + RELKIND_MATVIEW_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", @@ -939,9 +939,9 @@ static const SchemaQuery Query_for_list_of_indexables = { static const SchemaQuery Query_for_list_of_clusterables = { .catname = "pg_catalog.pg_class c", .selcondition = - "c.relkind IN (" CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) ", " - CppAsString2(RELKIND_MATVIEW) ")", + "c.relkind IN (" RELKIND_RELATION_STR ", " + RELKIND_PARTITIONED_TABLE_STR ", " + RELKIND_MATVIEW_STR ")", .viscondition = "pg_catalog.pg_table_is_visible(c.oid)", .namespace = "c.relnamespace", .result = "c.relname", diff --git a/src/bin/scripts/reindexdb.c b/src/bin/scripts/reindexdb.c index b15745256ff..e63dda7a7a1 100644 --- a/src/bin/scripts/reindexdb.c +++ b/src/bin/scripts/reindexdb.c @@ -651,8 +651,8 @@ get_parallel_tables_list(PGconn *conn, ReindexType type, " ON c.relnamespace = ns.oid\n" " WHERE ns.nspname != 'pg_catalog'\n" " AND c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) ")\n" + RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR ")\n" " AND c.relpersistence != " CppAsString2(RELPERSISTENCE_TEMP) "\n" " ORDER BY c.relpages DESC;"); @@ -674,8 +674,8 @@ get_parallel_tables_list(PGconn *conn, ReindexType type, " JOIN pg_catalog.pg_namespace ns" " ON c.relnamespace = ns.oid\n" " WHERE c.relkind IN (" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) ")\n" + RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR ")\n" " AND c.relpersistence != " CppAsString2(RELPERSISTENCE_TEMP) "\n" " AND ns.nspname IN ("); diff --git a/src/bin/scripts/vacuuming.c b/src/bin/scripts/vacuuming.c index faac9089a01..9c59cd31c50 100644 --- a/src/bin/scripts/vacuuming.c +++ b/src/bin/scripts/vacuuming.c @@ -598,8 +598,8 @@ retrieve_objects(PGconn *conn, vacuumingOptions *vacopts, " JOIN pg_catalog.pg_namespace ns" " ON c.relnamespace OPERATOR(pg_catalog.=) ns.oid\n" " CROSS JOIN LATERAL (SELECT c.relkind IN (" - CppAsString2(RELKIND_PARTITIONED_TABLE) ", " - CppAsString2(RELKIND_PARTITIONED_INDEX) ")) as p (inherited)\n" + RELKIND_PARTITIONED_TABLE_STR ", " + RELKIND_PARTITIONED_INDEX_STR ")) as p (inherited)\n" " LEFT JOIN pg_catalog.pg_class t" " ON c.reltoastrelid OPERATOR(pg_catalog.=) t.oid\n"); @@ -659,14 +659,14 @@ retrieve_objects(PGconn *conn, vacuumingOptions *vacopts, if (vacopts->mode == MODE_ANALYZE) appendPQExpBufferStr(&catalog_query, " AND c.relkind OPERATOR(pg_catalog.=) ANY (array[" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) ", " - CppAsString2(RELKIND_PARTITIONED_TABLE) "])\n"); + RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR ", " + RELKIND_PARTITIONED_TABLE_STR "])\n"); else appendPQExpBufferStr(&catalog_query, " AND c.relkind OPERATOR(pg_catalog.=) ANY (array[" - CppAsString2(RELKIND_RELATION) ", " - CppAsString2(RELKIND_MATVIEW) "])\n"); + RELKIND_RELATION_STR ", " + RELKIND_MATVIEW_STR "])\n"); } /* -- 2.47.3 --a5gwxv7edi5gnyjn Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="0003-Initial-steps-to-making-relkind-an-enum.patch" ^ permalink raw reply [nested|flat] 128+ messages in thread
end of thread, other threads:[~2026-02-01 23:45 UTC | newest] Thread overview: 128+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2019-03-07 20:49 [PATCH 2/3] Add operator <->(box, point) to GiST box_ops Nikita Glukhov <[email protected]> 2019-03-07 20:49 [PATCH 2/3] Add operator <->(box, point) to GiST box_ops Nikita Glukhov <[email protected]> 2019-03-07 20:49 [PATCH 2/3] Add operator <->(box, point) to GiST box_ops Nikita Glukhov <[email protected]> 2022-02-16 21:24 Preventing indirection for IndexPageGetOpaque for known-size page special areas Matthias van de Meent <[email protected]> 2022-03-28 04:31 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Michael Paquier <[email protected]> 2022-03-28 15:09 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Matthias van de Meent <[email protected]> 2022-03-31 07:32 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Michael Paquier <[email protected]> 2022-03-31 10:09 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Matthias van de Meent <[email protected]> 2022-04-01 05:38 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Michael Paquier <[email protected]> 2022-04-01 08:50 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Matthias van de Meent <[email protected]> 2022-04-01 15:12 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Matthias van de Meent <[email protected]> 2022-04-05 19:45 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Robert Haas <[email protected]> 2022-04-07 08:33 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Matthias van de Meent <[email protected]> 2022-04-07 14:01 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Robert Haas <[email protected]> 2022-04-07 18:42 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Peter Geoghegan <[email protected]> 2022-04-07 19:11 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Robert Haas <[email protected]> 2022-04-07 19:27 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Peter Geoghegan <[email protected]> 2022-04-07 19:37 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Robert Haas <[email protected]> 2022-04-07 20:09 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Stephen Frost <[email protected]> 2022-04-07 21:53 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Matthias van de Meent <[email protected]> 2022-04-18 20:04 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Bruce Momjian <[email protected]> 2022-11-28 22:31 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Tom Lane <[email protected]> 2022-11-29 00:22 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Michael Paquier <[email protected]> 2022-11-29 00:48 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Tom Lane <[email protected]> 2022-04-07 08:49 ` Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas Pavel Borisov <[email protected]> 2023-06-25 11:48 [PATCH v1 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-25 11:48 [PATCH v1 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-25 11:48 [PATCH v1 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-25 11:48 [PATCH v1 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-25 11:48 [PATCH v1 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-26 08:05 [PATCH v2 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-26 08:05 [PATCH v2 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-26 08:05 [PATCH v2 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-26 08:05 [PATCH v2 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-06-26 08:05 [PATCH v2 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-07-26 10:49 [PATCH v3 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-07-26 10:49 [PATCH v3 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-07-26 10:49 [PATCH v3 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-07-26 10:49 [PATCH v3 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-08-09 07:56 [PATCH v4 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-08-09 07:56 [PATCH v4 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-08-09 07:56 [PATCH v4 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-08-09 07:56 [PATCH v4 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-08-09 07:56 [PATCH v4 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-08-09 07:56 [PATCH v4 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-02 06:32 [PATCH v5 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-02 06:32 [PATCH v5 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-02 06:32 [PATCH v5 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-02 06:32 [PATCH v5 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-02 06:32 [PATCH v5 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-02 06:32 [PATCH v5 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-12 05:22 [PATCH v6 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-12 05:22 [PATCH v6 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-12 05:22 [PATCH v6 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-12 05:22 [PATCH v6 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-12 05:22 [PATCH v6 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-12 05:22 [PATCH v6 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-12 05:22 [PATCH v6 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-22 04:53 [PATCH v7 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-22 04:53 [PATCH v7 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-22 04:53 [PATCH v7 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-22 04:53 [PATCH v7 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-25 05:01 [PATCH v8 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-25 05:01 [PATCH v8 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-25 05:01 [PATCH v8 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-09-25 05:01 [PATCH v8 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-04 05:51 [PATCH v9 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-04 05:51 [PATCH v9 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-04 05:51 [PATCH v9 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-04 05:51 [PATCH v9 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-22 02:22 [PATCH v10 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-22 02:22 [PATCH v10 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-22 02:22 [PATCH v10 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-10-22 02:22 [PATCH v10 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-11-08 06:57 [PATCH v11 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-11-08 06:57 [PATCH v11 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-11-08 06:57 [PATCH v11 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-12-04 11:23 [PATCH v12 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-12-04 11:23 [PATCH v12 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2023-12-04 11:23 [PATCH v12 4/7] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-01-22 09:45 [PATCH v13 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-01-22 09:45 [PATCH v13 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-01-22 09:45 [PATCH v13 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-02-28 13:59 [PATCH v14 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-02-28 13:59 [PATCH v14 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-02-28 13:59 [PATCH v14 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-03-28 10:30 [PATCH v15 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-03-28 10:30 [PATCH v15 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-03-28 10:30 [PATCH v15 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-03-28 10:30 [PATCH v15 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-03-28 10:30 [PATCH v15 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-04-12 06:49 [PATCH v16 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-04-12 06:49 [PATCH v16 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-04-12 06:49 [PATCH v16 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-04-28 11:00 [PATCH v17 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-04-28 11:00 [PATCH v17 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-04-28 11:00 [PATCH v17 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-11 07:11 [PATCH v18 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-11 07:11 [PATCH v18 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-11 07:11 [PATCH v18 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-14 23:26 [PATCH v19 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-14 23:26 [PATCH v19 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-14 23:26 [PATCH v19 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-24 02:26 [PATCH v20 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-24 02:26 [PATCH v20 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-05-24 02:26 [PATCH v20 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-08-26 04:32 [PATCH v21 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-08-26 04:32 [PATCH v21 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-08-26 04:32 [PATCH v21 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-09-19 04:48 [PATCH v22 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-09-19 04:48 [PATCH v22 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-09-19 04:48 [PATCH v22 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-10-25 03:56 [PATCH v23 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-10-25 03:56 [PATCH v23 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-10-25 03:56 [PATCH v23 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-19 06:06 [PATCH v24 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-19 06:06 [PATCH v24 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-19 06:06 [PATCH v24 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-21 06:19 [PATCH v25 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-21 06:19 [PATCH v25 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-21 06:19 [PATCH v25 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-30 12:44 [PATCH v26 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-30 12:44 [PATCH v26 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-30 12:44 [PATCH v26 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-30 23:53 [PATCH v27 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-30 23:53 [PATCH v27 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2024-12-30 23:53 [PATCH v27 5/9] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]> 2026-02-01 23:45 [PATCH 2/3] replace CppAsString2(RELKIND_x) with RELKIND_x_STR Álvaro Herrera <[email protected]>
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