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[PATCH] Covering GiST v10
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* [PATCH] Covering GiST v10
@ 2019-01-30 00:59  Andreas Karlsson <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Andreas Karlsson @ 2019-01-30 00:59 UTC (permalink / raw)

This patch allow adding INCLUDE colums to GiST index.
These colums do not participate in GiST tree build,
are not used for chosing subtree for inserts or splits.
But they can be fetched during IndexOnlyScan.
---
 doc/src/sgml/ref/create_index.sgml                 |   4 +-
 doc/src/sgml/textsearch.sgml                       |   6 +
 src/backend/access/gist/gist.c                     |  33 +++-
 src/backend/access/gist/gistget.c                  |   4 +-
 src/backend/access/gist/gistscan.c                 |  12 +-
 src/backend/access/gist/gistsplit.c                |  12 +-
 src/backend/access/gist/gistutil.c                 |  42 ++++--
 src/include/access/gist_private.h                  |   2 +
 src/test/regress/expected/amutils.out              |   4 +-
 src/test/regress/expected/index_including.out      |   8 +-
 src/test/regress/expected/index_including_gist.out | 166 +++++++++++++++++++++
 src/test/regress/parallel_schedule                 |   2 +-
 src/test/regress/serial_schedule                   |   1 +
 src/test/regress/sql/index_including.sql           |   6 +-
 src/test/regress/sql/index_including_gist.sql      |  90 +++++++++++
 15 files changed, 358 insertions(+), 34 deletions(-)
 create mode 100644 src/test/regress/expected/index_including_gist.out
 create mode 100644 src/test/regress/sql/index_including_gist.sql

diff --git a/doc/src/sgml/ref/create_index.sgml b/doc/src/sgml/ref/create_index.sgml
index ad619cdcfe..f8657c6ae2 100644
--- a/doc/src/sgml/ref/create_index.sgml
+++ b/doc/src/sgml/ref/create_index.sgml
@@ -181,8 +181,8 @@ CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ [ IF NOT EXISTS ] <replaceable class=
        </para>
 
        <para>
-        Currently, only the B-tree index access method supports this feature.
-        In B-tree indexes, the values of columns listed in the
+        Currently, the B-tree and the GiST index access methods supports this
+        feature. In B-tree indexes, the values of columns listed in the
         <literal>INCLUDE</literal> clause are included in leaf tuples which
         correspond to heap tuples, but are not included in upper-level
         index entries used for tree navigation.
diff --git a/doc/src/sgml/textsearch.sgml b/doc/src/sgml/textsearch.sgml
index ecebade767..e4c75ebf6f 100644
--- a/doc/src/sgml/textsearch.sgml
+++ b/doc/src/sgml/textsearch.sgml
@@ -3675,6 +3675,12 @@ SELECT plainto_tsquery('supernovae stars');
   </para>
 
   <para>
+   A GiST index can be covering, i.e. use the <literal>INCLUDE</literal>
+   clause. Included columns can have data types without any GiST operator
+   class. Included attributes will be stored uncompressed.
+  </para>
+
+  <para>
    Lossiness causes performance degradation due to unnecessary fetches of table
    records that turn out to be false matches.  Since random access to table
    records is slow, this limits the usefulness of GiST indexes.  The
diff --git a/src/backend/access/gist/gist.c b/src/backend/access/gist/gist.c
index b75b3a8dac..2bbf7a7f49 100644
--- a/src/backend/access/gist/gist.c
+++ b/src/backend/access/gist/gist.c
@@ -75,7 +75,7 @@ gisthandler(PG_FUNCTION_ARGS)
 	amroutine->amclusterable = true;
 	amroutine->ampredlocks = true;
 	amroutine->amcanparallel = false;
-	amroutine->amcaninclude = false;
+	amroutine->amcaninclude = true;
 	amroutine->amkeytype = InvalidOid;
 
 	amroutine->ambuild = gistbuild;
@@ -1382,8 +1382,8 @@ gistSplit(Relation r,
 						IndexTupleSize(itup[0]), GiSTPageSize,
 						RelationGetRelationName(r))));
 
-	memset(v.spl_lisnull, true, sizeof(bool) * giststate->tupdesc->natts);
-	memset(v.spl_risnull, true, sizeof(bool) * giststate->tupdesc->natts);
+	memset(v.spl_lisnull, true, sizeof(bool) * giststate->truncTupdesc->natts);
+	memset(v.spl_risnull, true, sizeof(bool) * giststate->truncTupdesc->natts);
 	gistSplitByKey(r, page, itup, len, giststate, &v, 0);
 
 	/* form left and right vector */
@@ -1462,8 +1462,19 @@ initGISTstate(Relation index)
 	giststate->scanCxt = scanCxt;
 	giststate->tempCxt = scanCxt;	/* caller must change this if needed */
 	giststate->tupdesc = index->rd_att;
+	/*
+	 * The truncated tupdesc does not contain the INCLUDE attributes.
+	 *
+	 * It is used to form tuples during tuple adjustement and page split.
+	 * B-tree creates shortened tuple descriptor for every truncated tuple,
+	 * because it is doing this less often: it does not have to form
+	 * truncated tuples during page split. Also, B-tree is not adjusting
+	 * tuples on internal pages the way GiST does.
+	 */
+	giststate->truncTupdesc = CreateTupleDescCopyConstr(index->rd_att);
+	giststate->truncTupdesc->natts = IndexRelationGetNumberOfKeyAttributes(index);
 
-	for (i = 0; i < index->rd_att->natts; i++)
+	for (i = 0; i < IndexRelationGetNumberOfKeyAttributes(index); i++)
 	{
 		fmgr_info_copy(&(giststate->consistentFn[i]),
 					   index_getprocinfo(index, i + 1, GIST_CONSISTENT_PROC),
@@ -1531,6 +1542,20 @@ initGISTstate(Relation index)
 			giststate->supportCollation[i] = DEFAULT_COLLATION_OID;
 	}
 
+	for (; i < index->rd_att->natts; i++)
+	{
+		giststate->consistentFn[i].fn_oid = InvalidOid;
+		giststate->unionFn[i].fn_oid = InvalidOid;
+		giststate->compressFn[i].fn_oid = InvalidOid;
+		giststate->decompressFn[i].fn_oid = InvalidOid;
+		giststate->penaltyFn[i].fn_oid = InvalidOid;
+		giststate->picksplitFn[i].fn_oid = InvalidOid;
+		giststate->equalFn[i].fn_oid = InvalidOid;
+		giststate->distanceFn[i].fn_oid = InvalidOid;
+		giststate->fetchFn[i].fn_oid = InvalidOid;
+		giststate->supportCollation[i] = InvalidOid;
+	}
+
 	MemoryContextSwitchTo(oldCxt);
 
 	return giststate;
diff --git a/src/backend/access/gist/gistget.c b/src/backend/access/gist/gistget.c
index a96ef5c3ac..a4ee8763f6 100644
--- a/src/backend/access/gist/gistget.c
+++ b/src/backend/access/gist/gistget.c
@@ -769,11 +769,13 @@ gistgetbitmap(IndexScanDesc scan, TIDBitmap *tbm)
  *
  * Opclasses that implement a fetch function support index-only scans.
  * Opclasses without compression functions also support index-only scans.
+ * Included attributes always can be fetched for index-only scans.
  */
 bool
 gistcanreturn(Relation index, int attno)
 {
-	if (OidIsValid(index_getprocid(index, attno, GIST_FETCH_PROC)) ||
+	if (attno > IndexRelationGetNumberOfKeyAttributes(index) ||
+		OidIsValid(index_getprocid(index, attno, GIST_FETCH_PROC)) ||
 		!OidIsValid(index_getprocid(index, attno, GIST_COMPRESS_PROC)))
 		return true;
 	else
diff --git a/src/backend/access/gist/gistscan.c b/src/backend/access/gist/gistscan.c
index 78a8ede794..4fffc8b33a 100644
--- a/src/backend/access/gist/gistscan.c
+++ b/src/backend/access/gist/gistscan.c
@@ -158,6 +158,7 @@ gistrescan(IndexScanDesc scan, ScanKey key, int nkeys,
 	if (scan->xs_want_itup && !scan->xs_hitupdesc)
 	{
 		int			natts;
+		int			nkeyatts;
 		int			attno;
 
 		/*
@@ -167,13 +168,22 @@ gistrescan(IndexScanDesc scan, ScanKey key, int nkeys,
 		 * types.
 		 */
 		natts = RelationGetNumberOfAttributes(scan->indexRelation);
+		nkeyatts = IndexRelationGetNumberOfKeyAttributes(scan->indexRelation);
 		so->giststate->fetchTupdesc = CreateTemplateTupleDesc(natts);
-		for (attno = 1; attno <= natts; attno++)
+		for (attno = 1; attno <= nkeyatts; attno++)
 		{
 			TupleDescInitEntry(so->giststate->fetchTupdesc, attno, NULL,
 							   scan->indexRelation->rd_opcintype[attno - 1],
 							   -1, 0);
 		}
+
+		for (; attno <= natts; attno++)
+		{
+			/* taking opcintype from giststate->tupdesc */
+			TupleDescInitEntry(so->giststate->fetchTupdesc, attno, NULL,
+					TupleDescAttr(so->giststate->tupdesc, attno - 1)->atttypid,
+							   -1, 0);
+		}
 		scan->xs_hitupdesc = so->giststate->fetchTupdesc;
 
 		/* Also create a memory context that will hold the returned tuples */
diff --git a/src/backend/access/gist/gistsplit.c b/src/backend/access/gist/gistsplit.c
index f210e0c39f..cf3af2821a 100644
--- a/src/backend/access/gist/gistsplit.c
+++ b/src/backend/access/gist/gistsplit.c
@@ -207,7 +207,7 @@ placeOne(Relation r, GISTSTATE *giststate, GistSplitVector *v,
 	gistDeCompressAtt(giststate, r, itup, NULL, (OffsetNumber) 0,
 					  identry, isnull);
 
-	for (; attno < giststate->tupdesc->natts; attno++)
+	for (; attno < giststate->truncTupdesc->natts; attno++)
 	{
 		float		lpenalty,
 					rpenalty;
@@ -485,7 +485,7 @@ gistUserPicksplit(Relation r, GistEntryVector *entryvec, int attno, GistSplitVec
 	 */
 	v->spl_dontcare = NULL;
 
-	if (attno + 1 < giststate->tupdesc->natts)
+	if (attno + 1 < giststate->truncTupdesc->natts)
 	{
 		int			NumDontCare;
 
@@ -657,7 +657,7 @@ gistSplitByKey(Relation r, Page page, IndexTuple *itup, int len,
 		 */
 		v->spl_risnull[attno] = v->spl_lisnull[attno] = true;
 
-		if (attno + 1 < giststate->tupdesc->natts)
+		if (attno + 1 < giststate->truncTupdesc->natts)
 			gistSplitByKey(r, page, itup, len, giststate, v, attno + 1);
 		else
 			gistSplitHalf(&v->splitVector, len);
@@ -683,7 +683,7 @@ gistSplitByKey(Relation r, Page page, IndexTuple *itup, int len,
 				v->splitVector.spl_left[v->splitVector.spl_nleft++] = i;
 
 		/* Compute union keys, unless outer recursion level will handle it */
-		if (attno == 0 && giststate->tupdesc->natts == 1)
+		if (attno == 0 && giststate->truncTupdesc->natts == 1)
 		{
 			v->spl_dontcare = NULL;
 			gistunionsubkey(giststate, itup, v);
@@ -700,7 +700,7 @@ gistSplitByKey(Relation r, Page page, IndexTuple *itup, int len,
 			 * Splitting on attno column is not optimal, so consider
 			 * redistributing don't-care tuples according to the next column
 			 */
-			Assert(attno + 1 < giststate->tupdesc->natts);
+			Assert(attno + 1 < giststate->truncTupdesc->natts);
 
 			if (v->spl_dontcare == NULL)
 			{
@@ -771,7 +771,7 @@ gistSplitByKey(Relation r, Page page, IndexTuple *itup, int len,
 	 * that PickSplit (or the special cases above) produced correct union
 	 * datums.
 	 */
-	if (attno == 0 && giststate->tupdesc->natts > 1)
+	if (attno == 0 && giststate->truncTupdesc->natts > 1)
 	{
 		v->spl_dontcare = NULL;
 		gistunionsubkey(giststate, itup, v);
diff --git a/src/backend/access/gist/gistutil.c b/src/backend/access/gist/gistutil.c
index 8d3dfad27b..f7024eda12 100644
--- a/src/backend/access/gist/gistutil.c
+++ b/src/backend/access/gist/gistutil.c
@@ -160,7 +160,7 @@ gistMakeUnionItVec(GISTSTATE *giststate, IndexTuple *itvec, int len,
 
 	evec = (GistEntryVector *) palloc((len + 2) * sizeof(GISTENTRY) + GEVHDRSZ);
 
-	for (i = 0; i < giststate->tupdesc->natts; i++)
+	for (i = 0; i < giststate->truncTupdesc->natts; i++)
 	{
 		int			j;
 
@@ -296,7 +296,7 @@ gistDeCompressAtt(GISTSTATE *giststate, Relation r, IndexTuple tuple, Page p,
 {
 	int			i;
 
-	for (i = 0; i < r->rd_att->natts; i++)
+	for (i = 0; i < IndexRelationGetNumberOfKeyAttributes(r); i++)
 	{
 		Datum		datum;
 
@@ -329,7 +329,7 @@ gistgetadjusted(Relation r, IndexTuple oldtup, IndexTuple addtup, GISTSTATE *gis
 	gistDeCompressAtt(giststate, r, addtup, NULL,
 					  (OffsetNumber) 0, addentries, addisnull);
 
-	for (i = 0; i < r->rd_att->natts; i++)
+	for (i = 0; i < IndexRelationGetNumberOfKeyAttributes(r); i++)
 	{
 		gistMakeUnionKey(giststate, i,
 						 oldentries + i, oldisnull[i],
@@ -442,7 +442,7 @@ gistchoose(Relation r, Page p, IndexTuple it,	/* it has compressed entry */
 		zero_penalty = true;
 
 		/* Loop over index attributes. */
-		for (j = 0; j < r->rd_att->natts; j++)
+		for (j = 0; j < IndexRelationGetNumberOfKeyAttributes(r); j++)
 		{
 			Datum		datum;
 			float		usize;
@@ -470,7 +470,7 @@ gistchoose(Relation r, Page p, IndexTuple it,	/* it has compressed entry */
 				result = i;
 				best_penalty[j] = usize;
 
-				if (j < r->rd_att->natts - 1)
+				if (j < IndexRelationGetNumberOfKeyAttributes(r) - 1)
 					best_penalty[j + 1] = -1;
 
 				/* we have new best, so reset keep-it decision */
@@ -500,7 +500,7 @@ gistchoose(Relation r, Page p, IndexTuple it,	/* it has compressed entry */
 		 * If we looped past the last column, and did not update "result",
 		 * then this tuple is exactly as good as the prior best tuple.
 		 */
-		if (j == r->rd_att->natts && result != i)
+		if (j == IndexRelationGetNumberOfKeyAttributes(r) && result != i)
 		{
 			if (keep_current_best == -1)
 			{
@@ -575,11 +575,13 @@ gistFormTuple(GISTSTATE *giststate, Relation r,
 	Datum		compatt[INDEX_MAX_KEYS];
 	int			i;
 	IndexTuple	res;
+	/* currently we truncate tuples iif they are on internal pages */
+	bool isTruncated = !isleaf;
 
 	/*
 	 * Call the compress method on each attribute.
 	 */
-	for (i = 0; i < r->rd_att->natts; i++)
+	for (i = 0; i < IndexRelationGetNumberOfKeyAttributes(r); i++)
 	{
 		if (isnull[i])
 			compatt[i] = (Datum) 0;
@@ -602,7 +604,21 @@ gistFormTuple(GISTSTATE *giststate, Relation r,
 		}
 	}
 
-	res = index_form_tuple(giststate->tupdesc, compatt, isnull);
+	if (!isTruncated)
+	{
+		/*
+		 * Emplace each included attribute.
+		 */
+		for (; i < r->rd_att->natts; i++)
+		{
+			if (isnull[i])
+				compatt[i] = (Datum) 0;
+			else
+				compatt[i] = attdata[i];
+		}
+	}
+
+	res = index_form_tuple(isTruncated ? giststate->truncTupdesc : giststate->tupdesc, compatt, isnull);
 
 	/*
 	 * The offset number on tuples on internal pages is unused. For historical
@@ -644,7 +660,7 @@ gistFetchTuple(GISTSTATE *giststate, Relation r, IndexTuple tuple)
 	bool		isnull[INDEX_MAX_KEYS];
 	int			i;
 
-	for (i = 0; i < r->rd_att->natts; i++)
+	for (i = 0; i < IndexRelationGetNumberOfKeyAttributes(r); i++)
 	{
 		Datum		datum;
 
@@ -679,6 +695,14 @@ gistFetchTuple(GISTSTATE *giststate, Relation r, IndexTuple tuple)
 			fetchatt[i] = (Datum) 0;
 		}
 	}
+
+	/*
+	 * Get each included attribute.
+	 */
+	for (; i < r->rd_att->natts; i++)
+	{
+		fetchatt[i] = index_getattr(tuple, i + 1, giststate->tupdesc, &isnull[i]);
+	}
 	MemoryContextSwitchTo(oldcxt);
 
 	return heap_form_tuple(giststate->fetchTupdesc, fetchatt, isnull);
diff --git a/src/include/access/gist_private.h b/src/include/access/gist_private.h
index 3698942f9d..ccf06e676c 100644
--- a/src/include/access/gist_private.h
+++ b/src/include/access/gist_private.h
@@ -79,6 +79,8 @@ typedef struct GISTSTATE
 	MemoryContext tempCxt;		/* short-term context for calling functions */
 
 	TupleDesc	tupdesc;		/* index's tuple descriptor */
+	TupleDesc	truncTupdesc;	/* truncated tuple descriptor
+								 * for internal pages */
 	TupleDesc	fetchTupdesc;	/* tuple descriptor for tuples returned in an
 								 * index-only scan */
 
diff --git a/src/test/regress/expected/amutils.out b/src/test/regress/expected/amutils.out
index 4570a39b05..d92a6d12c6 100644
--- a/src/test/regress/expected/amutils.out
+++ b/src/test/regress/expected/amutils.out
@@ -75,7 +75,7 @@ select prop,
  can_unique         | f  |       | 
  can_multi_col      | t  |       | 
  can_exclude        | t  |       | 
- can_include        | f  |       | 
+ can_include        | t  |       | 
  bogus              |    |       | 
 (19 rows)
 
@@ -159,7 +159,7 @@ select amname, prop, pg_indexam_has_property(a.oid, prop) as p
  gist   | can_unique    | f
  gist   | can_multi_col | t
  gist   | can_exclude   | t
- gist   | can_include   | f
+ gist   | can_include   | t
  gist   | bogus         | 
  hash   | can_order     | f
  hash   | can_unique    | f
diff --git a/src/test/regress/expected/index_including.out b/src/test/regress/expected/index_including.out
index 16b4be34de..464629af88 100644
--- a/src/test/regress/expected/index_including.out
+++ b/src/test/regress/expected/index_including.out
@@ -313,22 +313,20 @@ SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl' ORDER BY indexname;
 
 DROP TABLE tbl;
 /*
- * 7. Check various AMs. All but btree must fail.
+ * 7. Check various AMs. All but btree and gist must fail.
  */
 CREATE TABLE tbl (c1 int,c2 int, c3 box, c4 box);
 CREATE INDEX on tbl USING brin(c1, c2) INCLUDE (c3, c4);
 ERROR:  access method "brin" does not support included columns
-CREATE INDEX on tbl USING gist(c3) INCLUDE (c4);
-ERROR:  access method "gist" does not support included columns
+CREATE INDEX on tbl USING gist(c3) INCLUDE (c1, c4);
 CREATE INDEX on tbl USING spgist(c3) INCLUDE (c4);
 ERROR:  access method "spgist" does not support included columns
 CREATE INDEX on tbl USING gin(c1, c2) INCLUDE (c3, c4);
 ERROR:  access method "gin" does not support included columns
 CREATE INDEX on tbl USING hash(c1, c2) INCLUDE (c3, c4);
 ERROR:  access method "hash" does not support included columns
-CREATE INDEX on tbl USING rtree(c1, c2) INCLUDE (c3, c4);
+CREATE INDEX on tbl USING rtree(c3) INCLUDE (c1, c4);
 NOTICE:  substituting access method "gist" for obsolete method "rtree"
-ERROR:  access method "gist" does not support included columns
 CREATE INDEX on tbl USING btree(c1, c2) INCLUDE (c3, c4);
 DROP TABLE tbl;
 /*
diff --git a/src/test/regress/expected/index_including_gist.out b/src/test/regress/expected/index_including_gist.out
new file mode 100644
index 0000000000..ed9906da66
--- /dev/null
+++ b/src/test/regress/expected/index_including_gist.out
@@ -0,0 +1,166 @@
+/*
+ * 1.1. test CREATE INDEX with buffered build
+ */
+-- Regular index with included columns
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+-- size is chosen to exceed page size and trigger actual truncation
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,8000) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c2,c3);
+SELECT pg_get_indexdef(i.indexrelid)
+FROM pg_index i JOIN pg_class c ON i.indexrelid = c.oid
+WHERE i.indrelid = 'tbl_gist'::regclass ORDER BY c.relname;
+                                  pg_get_indexdef                                  
+-----------------------------------------------------------------------------------
+ CREATE INDEX tbl_gist_idx ON public.tbl_gist USING gist (c4) INCLUDE (c1, c2, c3)
+(1 row)
+
+SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+ c1 | c2 | c3 |     c4      
+----+----+----+-------------
+  1 |  2 |  3 | (2,3),(1,2)
+  2 |  4 |  6 | (4,5),(2,3)
+  3 |  6 |  9 | (6,7),(3,4)
+  4 |  8 | 12 | (8,9),(4,5)
+(4 rows)
+
+SET enable_bitmapscan TO off;
+EXPLAIN  (costs off) SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+                   QUERY PLAN                   
+------------------------------------------------
+ Index Only Scan using tbl_gist_idx on tbl_gist
+   Index Cond: (c4 <@ '(10,10),(1,1)'::box)
+(2 rows)
+
+SET enable_bitmapscan TO default;
+DROP TABLE tbl_gist;
+/*
+ * 1.2. test CREATE INDEX with inserts
+ */
+-- Regular index with included columns
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+-- size is chosen to exceed page size and trigger actual truncation
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c2,c3);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,8000) AS x;
+SELECT pg_get_indexdef(i.indexrelid)
+FROM pg_index i JOIN pg_class c ON i.indexrelid = c.oid
+WHERE i.indrelid = 'tbl_gist'::regclass ORDER BY c.relname;
+                                  pg_get_indexdef                                  
+-----------------------------------------------------------------------------------
+ CREATE INDEX tbl_gist_idx ON public.tbl_gist USING gist (c4) INCLUDE (c1, c2, c3)
+(1 row)
+
+SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+ c1 | c2 | c3 |     c4      
+----+----+----+-------------
+  1 |  2 |  3 | (2,3),(1,2)
+  2 |  4 |  6 | (4,5),(2,3)
+  3 |  6 |  9 | (6,7),(3,4)
+  4 |  8 | 12 | (8,9),(4,5)
+(4 rows)
+
+SET enable_bitmapscan TO off;
+EXPLAIN  (costs off) SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+                   QUERY PLAN                   
+------------------------------------------------
+ Index Only Scan using tbl_gist_idx on tbl_gist
+   Index Cond: (c4 <@ '(10,10),(1,1)'::box)
+(2 rows)
+
+SET enable_bitmapscan TO default;
+DROP TABLE tbl_gist;
+/*
+ * 2. CREATE INDEX CONCURRENTLY
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX CONCURRENTLY tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c2,c3);
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+                                     indexdef                                      
+-----------------------------------------------------------------------------------
+ CREATE INDEX tbl_gist_idx ON public.tbl_gist USING gist (c4) INCLUDE (c1, c2, c3)
+(1 row)
+
+DROP TABLE tbl_gist;
+/*
+ * 3. REINDEX
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c3);
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+                                   indexdef                                    
+-------------------------------------------------------------------------------
+ CREATE INDEX tbl_gist_idx ON public.tbl_gist USING gist (c4) INCLUDE (c1, c3)
+(1 row)
+
+REINDEX INDEX tbl_gist_idx;
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+                                   indexdef                                    
+-------------------------------------------------------------------------------
+ CREATE INDEX tbl_gist_idx ON public.tbl_gist USING gist (c4) INCLUDE (c1, c3)
+(1 row)
+
+ALTER TABLE tbl_gist DROP COLUMN c1;
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+ indexdef 
+----------
+(0 rows)
+
+DROP TABLE tbl_gist;
+/*
+ * 4. Update, delete values in indexed table.
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c3);
+UPDATE tbl_gist SET c1 = 100 WHERE c1 = 2;
+UPDATE tbl_gist SET c1 = 1 WHERE c1 = 3;
+DELETE FROM tbl_gist WHERE c1 = 5 OR c3 = 12;
+DROP TABLE tbl_gist;
+/*
+ * 5. Alter column type.
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c3);
+ALTER TABLE tbl_gist ALTER c1 TYPE bigint;
+ALTER TABLE tbl_gist ALTER c3 TYPE bigint;
+\d tbl_gist
+              Table "public.tbl_gist"
+ Column |  Type   | Collation | Nullable | Default 
+--------+---------+-----------+----------+---------
+ c1     | bigint  |           |          | 
+ c2     | integer |           |          | 
+ c3     | bigint  |           |          | 
+ c4     | box     |           |          | 
+Indexes:
+    "tbl_gist_idx" gist (c4) INCLUDE (c1, c3)
+
+DROP TABLE tbl_gist;
+/*
+ * 6. EXCLUDE constraint.
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box, EXCLUDE USING gist (c4 WITH &&) INCLUDE (c1, c2, c3));
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+ERROR:  conflicting key value violates exclusion constraint "tbl_gist_c4_c1_c2_c3_excl"
+DETAIL:  Key (c4)=((4,5),(2,3)) conflicts with existing key (c4)=((2,3),(1,2)).
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(3*x,2*x),point(3*x+1,2*x+1)) FROM generate_series(1,10) AS x;
+EXPLAIN  (costs off) SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+                         QUERY PLAN                          
+-------------------------------------------------------------
+ Index Only Scan using tbl_gist_c4_c1_c2_c3_excl on tbl_gist
+   Index Cond: (c4 <@ '(10,10),(1,1)'::box)
+(2 rows)
+
+\d tbl_gist
+              Table "public.tbl_gist"
+ Column |  Type   | Collation | Nullable | Default 
+--------+---------+-----------+----------+---------
+ c1     | integer |           |          | 
+ c2     | integer |           |          | 
+ c3     | integer |           |          | 
+ c4     | box     |           |          | 
+Indexes:
+    "tbl_gist_c4_c1_c2_c3_excl" EXCLUDE USING gist (c4 WITH &&) INCLUDE (c1, c2, c3)
+
+DROP TABLE tbl_gist;
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index cc0bbf5db9..5684291ab0 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -55,7 +55,7 @@ test: copy copyselect copydml
 # ----------
 test: create_misc create_operator create_procedure
 # These depend on the above two
-test: create_index create_view index_including
+test: create_index create_view index_including index_including_gist
 
 # ----------
 # Another group of parallel tests
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index 0c10c7100c..309ccec81a 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -63,6 +63,7 @@ test: create_operator
 test: create_procedure
 test: create_index
 test: index_including
+test: index_including_gist
 test: create_view
 test: create_aggregate
 test: create_function_3
diff --git a/src/test/regress/sql/index_including.sql b/src/test/regress/sql/index_including.sql
index ef5fd882f5..3f9b9b51d7 100644
--- a/src/test/regress/sql/index_including.sql
+++ b/src/test/regress/sql/index_including.sql
@@ -173,15 +173,15 @@ SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl' ORDER BY indexname;
 DROP TABLE tbl;
 
 /*
- * 7. Check various AMs. All but btree must fail.
+ * 7. Check various AMs. All but btree and gist must fail.
  */
 CREATE TABLE tbl (c1 int,c2 int, c3 box, c4 box);
 CREATE INDEX on tbl USING brin(c1, c2) INCLUDE (c3, c4);
-CREATE INDEX on tbl USING gist(c3) INCLUDE (c4);
+CREATE INDEX on tbl USING gist(c3) INCLUDE (c1, c4);
 CREATE INDEX on tbl USING spgist(c3) INCLUDE (c4);
 CREATE INDEX on tbl USING gin(c1, c2) INCLUDE (c3, c4);
 CREATE INDEX on tbl USING hash(c1, c2) INCLUDE (c3, c4);
-CREATE INDEX on tbl USING rtree(c1, c2) INCLUDE (c3, c4);
+CREATE INDEX on tbl USING rtree(c3) INCLUDE (c1, c4);
 CREATE INDEX on tbl USING btree(c1, c2) INCLUDE (c3, c4);
 DROP TABLE tbl;
 
diff --git a/src/test/regress/sql/index_including_gist.sql b/src/test/regress/sql/index_including_gist.sql
new file mode 100644
index 0000000000..7d5c99b2e7
--- /dev/null
+++ b/src/test/regress/sql/index_including_gist.sql
@@ -0,0 +1,90 @@
+/*
+ * 1.1. test CREATE INDEX with buffered build
+ */
+
+-- Regular index with included columns
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+-- size is chosen to exceed page size and trigger actual truncation
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,8000) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c2,c3);
+SELECT pg_get_indexdef(i.indexrelid)
+FROM pg_index i JOIN pg_class c ON i.indexrelid = c.oid
+WHERE i.indrelid = 'tbl_gist'::regclass ORDER BY c.relname;
+SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+SET enable_bitmapscan TO off;
+EXPLAIN  (costs off) SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+SET enable_bitmapscan TO default;
+DROP TABLE tbl_gist;
+
+/*
+ * 1.2. test CREATE INDEX with inserts
+ */
+
+-- Regular index with included columns
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+-- size is chosen to exceed page size and trigger actual truncation
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c2,c3);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,8000) AS x;
+SELECT pg_get_indexdef(i.indexrelid)
+FROM pg_index i JOIN pg_class c ON i.indexrelid = c.oid
+WHERE i.indrelid = 'tbl_gist'::regclass ORDER BY c.relname;
+SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+SET enable_bitmapscan TO off;
+EXPLAIN  (costs off) SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+SET enable_bitmapscan TO default;
+DROP TABLE tbl_gist;
+
+/*
+ * 2. CREATE INDEX CONCURRENTLY
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX CONCURRENTLY tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c2,c3);
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+DROP TABLE tbl_gist;
+
+
+/*
+ * 3. REINDEX
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c3);
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+REINDEX INDEX tbl_gist_idx;
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+ALTER TABLE tbl_gist DROP COLUMN c1;
+SELECT indexdef FROM pg_indexes WHERE tablename = 'tbl_gist' ORDER BY indexname;
+DROP TABLE tbl_gist;
+
+/*
+ * 4. Update, delete values in indexed table.
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c3);
+UPDATE tbl_gist SET c1 = 100 WHERE c1 = 2;
+UPDATE tbl_gist SET c1 = 1 WHERE c1 = 3;
+DELETE FROM tbl_gist WHERE c1 = 5 OR c3 = 12;
+DROP TABLE tbl_gist;
+
+/*
+ * 5. Alter column type.
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box);
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+CREATE INDEX tbl_gist_idx ON tbl_gist using gist (c4) INCLUDE (c1,c3);
+ALTER TABLE tbl_gist ALTER c1 TYPE bigint;
+ALTER TABLE tbl_gist ALTER c3 TYPE bigint;
+\d tbl_gist
+DROP TABLE tbl_gist;
+
+/*
+ * 6. EXCLUDE constraint.
+ */
+CREATE TABLE tbl_gist (c1 int, c2 int, c3 int, c4 box, EXCLUDE USING gist (c4 WITH &&) INCLUDE (c1, c2, c3));
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(x,x+1),point(2*x,2*x+1)) FROM generate_series(1,10) AS x;
+INSERT INTO tbl_gist SELECT x, 2*x, 3*x, box(point(3*x,2*x),point(3*x+1,2*x+1)) FROM generate_series(1,10) AS x;
+EXPLAIN  (costs off) SELECT * FROM tbl_gist where c4 <@ box(point(1,1),point(10,10));
+\d tbl_gist
+DROP TABLE tbl_gist;
-- 
2.11.0


--------------509C046B61362466E7741578--




^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 19 +++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  4 ++++
 src/test/regress/expected/arrays.out | 19 +++++++++++++++++++
 src/test/regress/sql/arrays.sql      | 16 ++++++++++++++++
 4 files changed, 58 insertions(+)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 1ab31a9056..c3e157622f 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17916,6 +17916,25 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array to the elements 1 through <parameter>n</parameter>.  Usually these are
+        the first <parameter>n</parameter> elements of the array, but may not be if the lower
+        bound is different from 1.
+       </para>
+       <para>
+        <literal>select trim_array(ARRAY[1,2,3,4,5,6], 3)</literal>
+        <returnvalue>{1,2,3}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..0aae4daf3b 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,10 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819', descr => 'trim an array down to n elements',
+  proname => 'trim_array', prolang => 'sql', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'select ($1)[1:$2]' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..a79ad36cb0 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,22 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('{1,2,3,4,5,6}'),
+       ('[-15:-10]={1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 3)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |       trim_array       
+---------------------------------------------+------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {}
+ {1,2,3,4,5,6}                               | {1,2,3}
+ [10:15]={1,2,3,4,5,6}                       | {}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30}}
+(4 rows)
+
+DROP TABLE trim_array_test;
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..6d34cc468e 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,19 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('{1,2,3,4,5,6}'),
+       ('[-15:-10]={1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 3)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
-- 
2.25.1


--------------5C31E1109E6FF9DF4672B1B7--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 17 +++++++++++++++++
 src/include/catalog/pg_proc.dat      |  4 ++++
 src/test/regress/expected/arrays.out | 19 +++++++++++++++++++
 src/test/regress/sql/arrays.sql      | 16 ++++++++++++++++
 4 files changed, 56 insertions(+)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 1ab31a9056..58ab7860f4 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17916,6 +17916,23 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array to the first <parameter>n</parameter> elements.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 3)</literal>
+        <returnvalue>{1,2,3}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..76e2030865 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,10 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819', descr => 'trim an array down to n elements',
+  proname => 'trim_array', prolang => 'sql', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'select ($1)[:array_lower($1, 1) + $2 - 1]' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..3fb1b8dcef 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,22 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('{1,2,3,4,5,6}'),
+       ('[-15:-10]={1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 3)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |       trim_array       
+---------------------------------------------+------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3}
+ {1,2,3,4,5,6}                               | {1,2,3}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30}}
+(4 rows)
+
+DROP TABLE trim_array_test;
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..6d34cc468e 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,19 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('{1,2,3,4,5,6}'),
+       ('[-15:-10]={1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 3)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
-- 
2.25.1


--------------FD71656EDFD96EADB800280D--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 1ab31a9056..aa5026af07 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17916,6 +17916,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index a24387c1e7..b9863f04e9 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------A2B3F8F0E95C0C23ACC1AE0D--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH] implement trim_array
@ 2021-02-16 17:38  Vik Fearing <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Vik Fearing @ 2021-02-16 17:38 UTC (permalink / raw)

---
 doc/src/sgml/func.sgml               | 18 ++++++++++++
 src/backend/catalog/sql_features.txt |  2 +-
 src/backend/utils/adt/arrayfuncs.c   | 42 ++++++++++++++++++++++++++++
 src/include/catalog/pg_proc.dat      |  5 ++++
 src/test/regress/expected/arrays.out | 23 +++++++++++++++
 src/test/regress/sql/arrays.sql      | 19 +++++++++++++
 6 files changed, 108 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 08f08322ca..2aac87cf8d 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17909,6 +17909,24 @@ SELECT NULLIF(value, '(none)') ...
        </para></entry>
       </row>
 
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
       <row>
        <entry role="func_table_entry"><para role="func_signature">
         <indexterm>
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt
index ab0895ce3c..32eed988ab 100644
--- a/src/backend/catalog/sql_features.txt
+++ b/src/backend/catalog/sql_features.txt
@@ -398,7 +398,7 @@ S301	Enhanced UNNEST			YES
 S401	Distinct types based on array types			NO	
 S402	Distinct types based on distinct types			NO	
 S403	ARRAY_MAX_CARDINALITY			NO	
-S404	TRIM_ARRAY			NO	
+S404	TRIM_ARRAY			YES	
 T011	Timestamp in Information Schema			NO	
 T021	BINARY and VARBINARY data types			NO	
 T022	Advanced support for BINARY and VARBINARY data types			NO	
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index f7012cc5d9..d38a99f0b0 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -6631,3 +6631,45 @@ width_bucket_array_variable(Datum operand,
 
 	return left;
 }
+
+/*
+ * Trim the right N elements from an array by calculating an appropriate slice.
+ * Only the first dimension is trimmed.
+ */
+Datum
+trim_array(PG_FUNCTION_ARGS)
+{
+	ArrayType  *v = PG_GETARG_ARRAYTYPE_P(0);
+	int			n = PG_GETARG_INT32(1);
+	int			array_length = ARR_DIMS(v)[0];
+	int16		elmlen;
+	bool		elmbyval;
+	char		elmalign;
+	int			lower[MAXDIM];
+	int			upper[MAXDIM];
+	bool		lowerProvided[MAXDIM];
+	bool		upperProvided[MAXDIM];
+	Datum		result;
+
+	/* Throw an error if out of bounds */
+	if (n < 0 || n > array_length)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_ELEMENT_ERROR),
+				 errmsg("number of elements to trim must be between 0 and %d", array_length)));
+
+	/* Set all the bounds as unprovided except the first upper bound */
+	memset(lowerProvided, 0, sizeof(lowerProvided));
+	memset(upperProvided, 0, sizeof(upperProvided));
+	upper[0] = ARR_LBOUND(v)[0] + array_length - n - 1;
+	upperProvided[0] = true;
+
+	/* Fetch the needed information about the element type */
+	get_typlenbyvalalign(ARR_ELEMTYPE(v), &elmlen, &elmbyval, &elmalign);
+
+	/* Get the slice */
+	result = array_get_slice(PointerGetDatum(v), 1,
+							 upper, lower, upperProvided, lowerProvided,
+							 -1, elmlen, elmbyval, elmalign);
+
+	PG_RETURN_DATUM(result);
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 1487710d59..8ab911238d 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1674,6 +1674,11 @@
   proname => 'arraycontjoinsel', provolatile => 's', prorettype => 'float8',
   proargtypes => 'internal oid internal int2 internal',
   prosrc => 'arraycontjoinsel' },
+{ oid => '8819',
+  descr => 'trim an array down to n elements',
+  proname => 'trim_array', proisstrict => 't', provolatile => 'i',
+  prorettype => 'anyarray', proargtypes => 'anyarray int4',
+  prosrc => 'trim_array' },
 
 { oid => '764', descr => 'large object import',
   proname => 'lo_import', provolatile => 'v', proparallel => 'u',
diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 8bc7721e7d..fd3e4bfc49 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -2399,3 +2399,26 @@ SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 ERROR:  thresholds array must not contain NULLs
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
 ERROR:  thresholds must be one-dimensional array
+-- trim_array
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+                     arr                     |          trim_array           
+---------------------------------------------+-------------------------------
+ [-15:-10]={1,2,3,4,5,6}                     | {1,2,3,4}
+ {1,2,3,4,5,6}                               | {1,2,3,4}
+ [10:15]={1,2,3,4,5,6}                       | {1,2,3,4}
+ {{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}} | {{1,10},{2,20},{3,30},{4,40}}
+(4 rows)
+
+DROP TABLE trim_array_test;
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
+ERROR:  number of elements to trim must be between 0 and 3
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index c40619a8d5..551cf5c5c9 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -722,3 +722,22 @@ SELECT width_bucket(5, '{}');
 SELECT width_bucket('5'::text, ARRAY[3, 4]::integer[]);
 SELECT width_bucket(5, ARRAY[3, 4, NULL]);
 SELECT width_bucket(5, ARRAY[ARRAY[1, 2], ARRAY[3, 4]]);
+
+
+-- trim_array
+
+CREATE TABLE trim_array_test (arr integer[]);
+INSERT INTO trim_array_test
+VALUES ('[-15:-10]={1,2,3,4,5,6}'),
+       ('{1,2,3,4,5,6}'),
+       ('[10:15]={1,2,3,4,5,6}'),
+       ('{{1,10},{2,20},{3,30},{4,40},{5,50},{6,60}}');
+
+SELECT arr, trim_array(arr, 2)
+FROM trim_array_test
+ORDER BY arr;
+
+DROP TABLE trim_array_test;
+
+VALUES (trim_array(ARRAY[1, 2, 3], -1)); -- fail
+VALUES (trim_array(ARRAY[1, 2, 3], 10)); -- fail
-- 
2.25.1


--------------CD3F9594D6239C85433F5ED4--





^ permalink  raw  reply  [nested|flat] 29+ messages in thread

* [PATCH v23 1/8] Row pattern recognition patch for raw parser.
@ 2024-10-25 03:56  Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 29+ messages in thread

From: Tatsuo Ishii @ 2024-10-25 03:56 UTC (permalink / raw)

---
 src/backend/parser/gram.y       | 221 ++++++++++++++++++++++++++++++--
 src/include/nodes/parsenodes.h  |  67 ++++++++++
 src/include/parser/kwlist.h     |   8 ++
 src/include/parser/parse_node.h |   1 +
 4 files changed, 286 insertions(+), 11 deletions(-)

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index baca4059d2..ddfee6a652 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -664,6 +664,21 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 				json_object_constructor_null_clause_opt
 				json_array_constructor_null_clause_opt
 
+%type <target>	row_pattern_measure_item
+				row_pattern_definition
+%type <node>	opt_row_pattern_common_syntax
+				opt_row_pattern_skip_to
+				row_pattern_subset_item
+				row_pattern_term
+%type <list>	opt_row_pattern_measures
+				row_pattern_measure_list
+				row_pattern_definition_list
+				opt_row_pattern_subset_clause
+				row_pattern_subset_list
+				row_pattern_subset_rhs
+				row_pattern
+%type <boolean>	opt_row_pattern_initial_or_seek
+				first_or_last
 
 /*
  * Non-keyword token types.  These are hard-wired into the "flex" lexer.
@@ -707,7 +722,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	CURRENT_TIME CURRENT_TIMESTAMP CURRENT_USER CURSOR CYCLE
 
 	DATA_P DATABASE DAY_P DEALLOCATE DEC DECIMAL_P DECLARE DEFAULT DEFAULTS
-	DEFERRABLE DEFERRED DEFINER DELETE_P DELIMITER DELIMITERS DEPENDS DEPTH DESC
+	DEFERRABLE DEFERRED DEFINE DEFINER DELETE_P DELIMITER DELIMITERS DEPENDS DEPTH DESC
 	DETACH DICTIONARY DISABLE_P DISCARD DISTINCT DO DOCUMENT_P DOMAIN_P
 	DOUBLE_P DROP
 
@@ -723,7 +738,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	HANDLER HAVING HEADER_P HOLD HOUR_P
 
 	IDENTITY_P IF_P ILIKE IMMEDIATE IMMUTABLE IMPLICIT_P IMPORT_P IN_P INCLUDE
-	INCLUDING INCREMENT INDENT INDEX INDEXES INHERIT INHERITS INITIALLY INLINE_P
+	INCLUDING INCREMENT INDENT INDEX INDEXES INHERIT INHERITS INITIAL INITIALLY INLINE_P
 	INNER_P INOUT INPUT_P INSENSITIVE INSERT INSTEAD INT_P INTEGER
 	INTERSECT INTERVAL INTO INVOKER IS ISNULL ISOLATION
 
@@ -736,7 +751,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	LEADING LEAKPROOF LEAST LEFT LEVEL LIKE LIMIT LISTEN LOAD LOCAL
 	LOCALTIME LOCALTIMESTAMP LOCATION LOCK_P LOCKED LOGGED
 
-	MAPPING MATCH MATCHED MATERIALIZED MAXVALUE MERGE MERGE_ACTION METHOD
+	MAPPING MATCH MATCHED MATERIALIZED MAXVALUE MEASURES MERGE MERGE_ACTION METHOD
 	MINUTE_P MINVALUE MODE MONTH_P MOVE
 
 	NAME_P NAMES NATIONAL NATURAL NCHAR NESTED NEW NEXT NFC NFD NFKC NFKD NO
@@ -748,8 +763,9 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	ORDER ORDINALITY OTHERS OUT_P OUTER_P
 	OVER OVERLAPS OVERLAY OVERRIDING OWNED OWNER
 
-	PARALLEL PARAMETER PARSER PARTIAL PARTITION PASSING PASSWORD PATH
-	PERIOD PLACING PLAN PLANS POLICY
+	PARALLEL PARAMETER PARSER PARTIAL PARTITION PASSING PASSWORD PAST
+	PATH PATTERN_P PERIOD PERMUTE PLACING PLAN PLANS POLICY
+
 	POSITION PRECEDING PRECISION PRESERVE PREPARE PREPARED PRIMARY
 	PRIOR PRIVILEGES PROCEDURAL PROCEDURE PROCEDURES PROGRAM PUBLICATION
 
@@ -760,12 +776,13 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 	RESET RESTART RESTRICT RETURN RETURNING RETURNS REVOKE RIGHT ROLE ROLLBACK ROLLUP
 	ROUTINE ROUTINES ROW ROWS RULE
 
-	SAVEPOINT SCALAR SCHEMA SCHEMAS SCROLL SEARCH SECOND_P SECURITY SELECT
+	SAVEPOINT SCALAR SCHEMA SCHEMAS SCROLL SEARCH SECOND_P SECURITY SEEK SELECT
 	SEQUENCE SEQUENCES
+
 	SERIALIZABLE SERVER SESSION SESSION_USER SET SETS SETOF SHARE SHOW
 	SIMILAR SIMPLE SKIP SMALLINT SNAPSHOT SOME SOURCE SQL_P STABLE STANDALONE_P
 	START STATEMENT STATISTICS STDIN STDOUT STORAGE STORED STRICT_P STRING_P STRIP_P
-	SUBSCRIPTION SUBSTRING SUPPORT SYMMETRIC SYSID SYSTEM_P SYSTEM_USER
+	SUBSCRIPTION SUBSET SUBSTRING SUPPORT SYMMETRIC SYSID SYSTEM_P SYSTEM_USER
 
 	TABLE TABLES TABLESAMPLE TABLESPACE TARGET TEMP TEMPLATE TEMPORARY TEXT_P THEN
 	TIES TIME TIMESTAMP TO TRAILING TRANSACTION TRANSFORM
@@ -874,6 +891,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 %nonassoc	UNBOUNDED NESTED /* ideally would have same precedence as IDENT */
 %nonassoc	IDENT PARTITION RANGE ROWS GROUPS PRECEDING FOLLOWING CUBE ROLLUP
 			SET KEYS OBJECT_P SCALAR VALUE_P WITH WITHOUT PATH
+			MEASURES AFTER INITIAL SEEK PATTERN_P
 %left		Op OPERATOR		/* multi-character ops and user-defined operators */
 %left		'+' '-'
 %left		'*' '/' '%'
@@ -16279,7 +16297,8 @@ over_clause: OVER window_specification
 		;
 
 window_specification: '(' opt_existing_window_name opt_partition_clause
-						opt_sort_clause opt_frame_clause ')'
+						opt_sort_clause opt_row_pattern_measures opt_frame_clause
+						opt_row_pattern_common_syntax ')'
 				{
 					WindowDef  *n = makeNode(WindowDef);
 
@@ -16287,10 +16306,12 @@ window_specification: '(' opt_existing_window_name opt_partition_clause
 					n->refname = $2;
 					n->partitionClause = $3;
 					n->orderClause = $4;
+					n->rowPatternMeasures = $5;
 					/* copy relevant fields of opt_frame_clause */
-					n->frameOptions = $5->frameOptions;
-					n->startOffset = $5->startOffset;
-					n->endOffset = $5->endOffset;
+					n->frameOptions = $6->frameOptions;
+					n->startOffset = $6->startOffset;
+					n->endOffset = $6->endOffset;
+					n->rpCommonSyntax = (RPCommonSyntax *)$7;
 					n->location = @1;
 					$$ = n;
 				}
@@ -16314,6 +16335,31 @@ opt_partition_clause: PARTITION BY expr_list		{ $$ = $3; }
 			| /*EMPTY*/								{ $$ = NIL; }
 		;
 
+/*
+ * ROW PATTERN_P MEASURES
+ */
+opt_row_pattern_measures: MEASURES row_pattern_measure_list	{ $$ = $2; }
+			| /*EMPTY*/								{ $$ = NIL; }
+		;
+
+row_pattern_measure_list:
+			row_pattern_measure_item
+					{ $$ = list_make1($1); }
+			| row_pattern_measure_list ',' row_pattern_measure_item
+					{ $$ = lappend($1, $3); }
+		;
+
+row_pattern_measure_item:
+			a_expr AS ColLabel
+				{
+					$$ = makeNode(ResTarget);
+					$$->name = $3;
+					$$->indirection = NIL;
+					$$->val = (Node *) $1;
+					$$->location = @1;
+				}
+		;
+
 /*
  * For frame clauses, we return a WindowDef, but only some fields are used:
  * frameOptions, startOffset, and endOffset.
@@ -16473,6 +16519,143 @@ opt_window_exclusion_clause:
 			| /*EMPTY*/				{ $$ = 0; }
 		;
 
+opt_row_pattern_common_syntax:
+opt_row_pattern_skip_to opt_row_pattern_initial_or_seek
+				PATTERN_P '(' row_pattern ')'
+				opt_row_pattern_subset_clause
+				DEFINE row_pattern_definition_list
+			{
+				RPCommonSyntax *n = makeNode(RPCommonSyntax);
+				n->rpSkipTo = ((RPCommonSyntax *)$1)->rpSkipTo;
+				n->rpSkipVariable = ((RPCommonSyntax *)$1)->rpSkipVariable;
+				n->initial = $2;
+				n->rpPatterns = $5;
+				n->rpSubsetClause = $7;
+				n->rpDefs = $9;
+				$$ = (Node *) n;
+			}
+			| /*EMPTY*/		{ $$ = NULL; }
+	;
+
+opt_row_pattern_skip_to:
+			AFTER MATCH SKIP TO NEXT ROW
+				{
+					RPCommonSyntax *n = makeNode(RPCommonSyntax);
+					n->rpSkipTo = ST_NEXT_ROW;
+					n->rpSkipVariable = NULL;
+					$$ = (Node *) n;
+			}
+			| AFTER MATCH SKIP PAST LAST_P ROW
+				{
+					RPCommonSyntax *n = makeNode(RPCommonSyntax);
+					n->rpSkipTo = ST_PAST_LAST_ROW;
+					n->rpSkipVariable = NULL;
+					$$ = (Node *) n;
+				}
+			| AFTER MATCH SKIP TO first_or_last ColId
+				{
+					RPCommonSyntax *n = makeNode(RPCommonSyntax);
+					n->rpSkipTo = $5? ST_FIRST_VARIABLE : ST_LAST_VARIABLE;
+					n->rpSkipVariable = $6;
+					$$ = (Node *) n;
+				}
+/*
+			| AFTER MATCH SKIP TO LAST_P ColId		%prec LAST_P
+				{
+					RPCommonSyntax *n = makeNode(RPCommonSyntax);
+					n->rpSkipTo = ST_LAST_VARIABLE;
+					n->rpSkipVariable = $6;
+					$$ = n;
+				}
+			| AFTER MATCH SKIP TO ColId
+				{
+					RPCommonSyntax *n = makeNode(RPCommonSyntax);
+					n->rpSkipTo = ST_VARIABLE;
+					n->rpSkipVariable = $5;
+					$$ = n;
+				}
+*/
+			| /*EMPTY*/
+				{
+					RPCommonSyntax *n = makeNode(RPCommonSyntax);
+					/* temporary set default to ST_NEXT_ROW */
+					n->rpSkipTo = ST_PAST_LAST_ROW;
+					n->rpSkipVariable = NULL;
+					$$ = (Node *) n;
+				}
+	;
+
+first_or_last:
+			FIRST_P		{ $$ = true; }
+			| LAST_P	{ $$ = false; }
+	;
+
+opt_row_pattern_initial_or_seek:
+			INITIAL			{ $$ = true; }
+			| SEEK
+				{
+					ereport(ERROR,
+							(errcode(ERRCODE_SYNTAX_ERROR),
+							 errmsg("SEEK is not supported"),
+							 errhint("Use INITIAL."),
+							 parser_errposition(@1)));
+				}
+			| /*EMPTY*/		{ $$ = true; }
+		;
+
+row_pattern:
+			row_pattern_term							{ $$ = list_make1($1); }
+			| row_pattern row_pattern_term				{ $$ = lappend($1, $2); }
+		;
+
+row_pattern_term:
+			ColId	{ $$ = (Node *) makeSimpleA_Expr(AEXPR_OP, "", (Node *)makeString($1), NULL, @1); }
+			| ColId '*'	{ $$ = (Node *) makeSimpleA_Expr(AEXPR_OP, "*", (Node *)makeString($1), NULL, @1); }
+			| ColId '+'	{ $$ = (Node *) makeSimpleA_Expr(AEXPR_OP, "+", (Node *)makeString($1), NULL, @1); }
+			| ColId '?'	{ $$ = (Node *) makeSimpleA_Expr(AEXPR_OP, "?", (Node *)makeString($1), NULL, @1); }
+		;
+
+opt_row_pattern_subset_clause:
+			SUBSET row_pattern_subset_list	{ $$ = $2; }
+			| /*EMPTY*/												{ $$ = NIL; }
+		;
+
+row_pattern_subset_list:
+			row_pattern_subset_item									{ $$ = list_make1($1); }
+			| row_pattern_subset_list ',' row_pattern_subset_item	{ $$ = lappend($1, $3); }
+			| /*EMPTY*/												{ $$ = NIL; }
+		;
+
+row_pattern_subset_item: ColId '=' '(' row_pattern_subset_rhs ')'
+			{
+				RPSubsetItem *n = makeNode(RPSubsetItem);
+				n->name = $1;
+				n->rhsVariable = $4;
+				$$ = (Node *) n;
+			}
+		;
+
+row_pattern_subset_rhs:
+			ColId								{ $$ = list_make1(makeStringConst($1, @1)); }
+			| row_pattern_subset_rhs ',' ColId	{ $$ = lappend($1, makeStringConst($3, @1)); }
+			| /*EMPTY*/							{ $$ = NIL; }
+		;
+
+row_pattern_definition_list:
+			row_pattern_definition										{ $$ = list_make1($1); }
+			| row_pattern_definition_list ',' row_pattern_definition	{ $$ = lappend($1, $3); }
+		;
+
+row_pattern_definition:
+			ColId AS a_expr
+				{
+					$$ = makeNode(ResTarget);
+					$$->name = $1;
+					$$->indirection = NIL;
+					$$->val = (Node *) $3;
+					$$->location = @1;
+				}
+		;
 
 /*
  * Supporting nonterminals for expressions.
@@ -17683,6 +17866,7 @@ unreserved_keyword:
 			| INDEXES
 			| INHERIT
 			| INHERITS
+			| INITIAL
 			| INLINE_P
 			| INPUT_P
 			| INSENSITIVE
@@ -17711,6 +17895,7 @@ unreserved_keyword:
 			| MATCHED
 			| MATERIALIZED
 			| MAXVALUE
+			| MEASURES
 			| MERGE
 			| METHOD
 			| MINUTE_P
@@ -17755,8 +17940,11 @@ unreserved_keyword:
 			| PARTITION
 			| PASSING
 			| PASSWORD
+			| PAST
 			| PATH
+			| PATTERN_P
 			| PERIOD
+			| PERMUTE
 			| PLAN
 			| PLANS
 			| POLICY
@@ -17808,6 +17996,7 @@ unreserved_keyword:
 			| SEARCH
 			| SECOND_P
 			| SECURITY
+			| SEEK
 			| SEQUENCE
 			| SEQUENCES
 			| SERIALIZABLE
@@ -17835,6 +18024,7 @@ unreserved_keyword:
 			| STRING_P
 			| STRIP_P
 			| SUBSCRIPTION
+			| SUBSET
 			| SUPPORT
 			| SYSID
 			| SYSTEM_P
@@ -18029,6 +18219,7 @@ reserved_keyword:
 			| CURRENT_USER
 			| DEFAULT
 			| DEFERRABLE
+			| DEFINE
 			| DESC
 			| DISTINCT
 			| DO
@@ -18192,6 +18383,7 @@ bare_label_keyword:
 			| DEFAULTS
 			| DEFERRABLE
 			| DEFERRED
+			| DEFINE
 			| DEFINER
 			| DELETE_P
 			| DELIMITER
@@ -18269,6 +18461,7 @@ bare_label_keyword:
 			| INDEXES
 			| INHERIT
 			| INHERITS
+			| INITIAL
 			| INITIALLY
 			| INLINE_P
 			| INNER_P
@@ -18323,6 +18516,7 @@ bare_label_keyword:
 			| MATCHED
 			| MATERIALIZED
 			| MAXVALUE
+			| MEASURES
 			| MERGE
 			| MERGE_ACTION
 			| METHOD
@@ -18379,8 +18573,11 @@ bare_label_keyword:
 			| PARTITION
 			| PASSING
 			| PASSWORD
+			| PAST
 			| PATH
+			| PATTERN_P
 			| PERIOD
+			| PERMUTE
 			| PLACING
 			| PLAN
 			| PLANS
@@ -18438,6 +18635,7 @@ bare_label_keyword:
 			| SCROLL
 			| SEARCH
 			| SECURITY
+			| SEEK
 			| SELECT
 			| SEQUENCE
 			| SEQUENCES
@@ -18471,6 +18669,7 @@ bare_label_keyword:
 			| STRING_P
 			| STRIP_P
 			| SUBSCRIPTION
+			| SUBSET
 			| SUBSTRING
 			| SUPPORT
 			| SYMMETRIC
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index b40b661ec8..685ca438b1 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -552,6 +552,48 @@ typedef struct SortBy
 	ParseLoc	location;		/* operator location, or -1 if none/unknown */
 } SortBy;
 
+/*
+ * AFTER MATCH row pattern skip to types in row pattern common syntax
+ */
+typedef enum RPSkipTo
+{
+	ST_NONE,					/* AFTER MATCH omitted */
+	ST_NEXT_ROW,				/* SKIP TO NEXT ROW */
+	ST_PAST_LAST_ROW,			/* SKIP TO PAST LAST ROW */
+	ST_FIRST_VARIABLE,			/* SKIP TO FIRST variable name */
+	ST_LAST_VARIABLE,			/* SKIP TO LAST variable name */
+	ST_VARIABLE					/* SKIP TO variable name */
+}			RPSkipTo;
+
+/*
+ * Row Pattern SUBSET clause item
+ */
+typedef struct RPSubsetItem
+{
+	NodeTag		type;
+	char	   *name;			/* Row Pattern SUBSET clause variable name */
+	List	   *rhsVariable;	/* Row Pattern SUBSET rhs variables (list of
+								 * char *string) */
+}			RPSubsetItem;
+
+/*
+ * RowPatternCommonSyntax - raw representation of row pattern common syntax
+ *
+ */
+typedef struct RPCommonSyntax
+{
+	NodeTag		type;
+	RPSkipTo	rpSkipTo;		/* Row Pattern AFTER MATCH SKIP type */
+	char	   *rpSkipVariable; /* Row Pattern Skip To variable name, if any */
+	bool		initial;		/* true if <row pattern initial or seek> is
+								 * initial */
+	List	   *rpPatterns;		/* PATTERN variables (list of A_Expr) */
+	List	   *rpSubsetClause; /* row pattern subset clause (list of
+								 * RPSubsetItem), if any */
+	List	   *rpDefs;			/* row pattern definitions clause (list of
+								 * ResTarget) */
+}			RPCommonSyntax;
+
 /*
  * WindowDef - raw representation of WINDOW and OVER clauses
  *
@@ -567,6 +609,9 @@ typedef struct WindowDef
 	char	   *refname;		/* referenced window name, if any */
 	List	   *partitionClause;	/* PARTITION BY expression list */
 	List	   *orderClause;	/* ORDER BY (list of SortBy) */
+	List	   *rowPatternMeasures; /* row pattern measures (list of
+									 * ResTarget) */
+	RPCommonSyntax *rpCommonSyntax; /* row pattern common syntax */
 	int			frameOptions;	/* frame_clause options, see below */
 	Node	   *startOffset;	/* expression for starting bound, if any */
 	Node	   *endOffset;		/* expression for ending bound, if any */
@@ -1530,6 +1575,11 @@ typedef struct GroupingSet
  * the orderClause might or might not be copied (see copiedOrder); the framing
  * options are never copied, per spec.
  *
+ * "defineClause" is Row Pattern Recognition DEFINE clause (list of
+ * TargetEntry). TargetEntry.resname represents row pattern definition
+ * variable name. "patternVariable" and "patternRegexp" represents PATTERN
+ * clause.
+ *
  * The information relevant for the query jumbling is the partition clause
  * type and its bounds.
  */
@@ -1559,6 +1609,23 @@ typedef struct WindowClause
 	Index		winref;			/* ID referenced by window functions */
 	/* did we copy orderClause from refname? */
 	bool		copiedOrder pg_node_attr(query_jumble_ignore);
+	/* Row Pattern AFTER MACH SKIP clause */
+	RPSkipTo	rpSkipTo;		/* Row Pattern Skip To type */
+	char	   *rpSkipVariable; /* Row Pattern Skip To variable */
+	bool		initial;		/* true if <row pattern initial or seek> is
+								 * initial */
+	/* Row Pattern DEFINE clause (list of TargetEntry) */
+	List	   *defineClause;
+	/* Row Pattern DEFINE variable initial names (list of String) */
+	List	   *defineInitial;
+	/* Row Pattern PATTERN variable name (list of String) */
+	List	   *patternVariable;
+
+	/*
+	 * Row Pattern PATTERN regular expression quantifier ('+' or ''. list of
+	 * String)
+	 */
+	List	   *patternRegexp;
 } WindowClause;
 
 /*
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h
index 899d64ad55..f52d797615 100644
--- a/src/include/parser/kwlist.h
+++ b/src/include/parser/kwlist.h
@@ -129,6 +129,7 @@ PG_KEYWORD("default", DEFAULT, RESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("defaults", DEFAULTS, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("deferrable", DEFERRABLE, RESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("deferred", DEFERRED, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("define", DEFINE, RESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("definer", DEFINER, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("delete", DELETE_P, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("delimiter", DELIMITER, UNRESERVED_KEYWORD, BARE_LABEL)
@@ -215,6 +216,7 @@ PG_KEYWORD("index", INDEX, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("indexes", INDEXES, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("inherit", INHERIT, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("inherits", INHERITS, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("initial", INITIAL, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("initially", INITIALLY, RESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("inline", INLINE_P, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("inner", INNER_P, TYPE_FUNC_NAME_KEYWORD, BARE_LABEL)
@@ -273,6 +275,7 @@ PG_KEYWORD("match", MATCH, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("matched", MATCHED, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("materialized", MATERIALIZED, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("maxvalue", MAXVALUE, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("measures", MEASURES, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("merge", MERGE, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("merge_action", MERGE_ACTION, COL_NAME_KEYWORD, BARE_LABEL)
 PG_KEYWORD("method", METHOD, UNRESERVED_KEYWORD, BARE_LABEL)
@@ -337,8 +340,11 @@ PG_KEYWORD("partial", PARTIAL, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("partition", PARTITION, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("passing", PASSING, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("password", PASSWORD, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("past", PAST, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("path", PATH, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("pattern", PATTERN_P, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("period", PERIOD, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("permute", PERMUTE, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("placing", PLACING, RESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("plan", PLAN, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("plans", PLANS, UNRESERVED_KEYWORD, BARE_LABEL)
@@ -399,6 +405,7 @@ PG_KEYWORD("scroll", SCROLL, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("search", SEARCH, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("second", SECOND_P, UNRESERVED_KEYWORD, AS_LABEL)
 PG_KEYWORD("security", SECURITY, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("seek", SEEK, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("select", SELECT, RESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("sequence", SEQUENCE, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("sequences", SEQUENCES, UNRESERVED_KEYWORD, BARE_LABEL)
@@ -432,6 +439,7 @@ PG_KEYWORD("strict", STRICT_P, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("string", STRING_P, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("strip", STRIP_P, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("subscription", SUBSCRIPTION, UNRESERVED_KEYWORD, BARE_LABEL)
+PG_KEYWORD("subset", SUBSET, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("substring", SUBSTRING, COL_NAME_KEYWORD, BARE_LABEL)
 PG_KEYWORD("support", SUPPORT, UNRESERVED_KEYWORD, BARE_LABEL)
 PG_KEYWORD("symmetric", SYMMETRIC, RESERVED_KEYWORD, BARE_LABEL)
diff --git a/src/include/parser/parse_node.h b/src/include/parser/parse_node.h
index 2375e95c10..737f8a9e0e 100644
--- a/src/include/parser/parse_node.h
+++ b/src/include/parser/parse_node.h
@@ -51,6 +51,7 @@ typedef enum ParseExprKind
 	EXPR_KIND_WINDOW_FRAME_RANGE,	/* window frame clause with RANGE */
 	EXPR_KIND_WINDOW_FRAME_ROWS,	/* window frame clause with ROWS */
 	EXPR_KIND_WINDOW_FRAME_GROUPS,	/* window frame clause with GROUPS */
+	EXPR_KIND_RPR_DEFINE,		/* DEFINE */
 	EXPR_KIND_SELECT_TARGET,	/* SELECT target list item */
 	EXPR_KIND_INSERT_TARGET,	/* INSERT target list item */
 	EXPR_KIND_UPDATE_SOURCE,	/* UPDATE assignment source item */
-- 
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="v23-0002-Row-pattern-recognition-patch-parse-analysis.patch"



^ permalink  raw  reply  [nested|flat] 29+ messages in thread


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Thread overview: 29+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2019-01-30 00:59 [PATCH] Covering GiST v10 Andreas Karlsson <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2021-02-16 17:38 [PATCH] implement trim_array Vik Fearing <[email protected]>
2024-10-25 03:56 [PATCH v23 1/8] Row pattern recognition patch for raw parser. Tatsuo Ishii <[email protected]>

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