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* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-29 16:46 Nathan Bossart <[email protected]>
0 siblings, 1 reply; 12+ messages in thread
From: Nathan Bossart @ 2023-08-29 16:46 UTC (permalink / raw)
To: Michael Paquier <[email protected]>; +Cc: Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers; [email protected] <[email protected]>
On Mon, Aug 28, 2023 at 10:53:52AM +0900, Michael Paquier wrote:
> I understand that this is not a fantastic naming, but renaming
> pgstat_fetch_stat_local_beentry() to something like
> pgstat_fetch_stat_local_beentry_by_{index|position}_id() would make
> the difference much easier to grasp, and we should avoid the use of
> "beid" when we refer to the *position/index ID* in
> localBackendStatusTable, because it is not a BackendId at all, just a
> position in the local array.
This was my first reaction [0]. I was concerned about renaming the
exported functions so close to release, so I was suggesting that we hold
off on that part until v17. If there isn't a concern with renaming these
functions in v16, I can proceed with something more like v2.
[0] https://postgr.es/m/20230824161913.GA1394441%40nathanxps13.lan
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-29 23:22 Michael Paquier <[email protected]>
parent: Nathan Bossart <[email protected]>
0 siblings, 1 reply; 12+ messages in thread
From: Michael Paquier @ 2023-08-29 23:22 UTC (permalink / raw)
To: Nathan Bossart <[email protected]>; +Cc: Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers; [email protected] <[email protected]>
On Tue, Aug 29, 2023 at 09:46:55AM -0700, Nathan Bossart wrote:
> This was my first reaction [0]. I was concerned about renaming the
> exported functions so close to release, so I was suggesting that we hold
> off on that part until v17. If there isn't a concern with renaming these
> functions in v16, I can proceed with something more like v2.
Thanks for the pointer. This version is much better IMO, because it
removes entirely the source of the confusion between the difference in
backend ID and index ID treatments when fetching the local entries in
the array. So I'm okay to rename these functions now, before .0 is
released to get things in a better shape while addressing the issue
reported.
+extern LocalPgBackendStatus *pgstat_get_local_beentry_by_index(int beid);
Still I would to a bit more of s/beid/id/ for cases where the code
refers to an index ID, and not a backend ID, especially for the
internal routines.
--
Michael
Attachments:
[application/pgp-signature] signature.asc (833B, ../../[email protected]/2-signature.asc)
download
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-30 02:01 Nathan Bossart <[email protected]>
parent: Michael Paquier <[email protected]>
0 siblings, 1 reply; 12+ messages in thread
From: Nathan Bossart @ 2023-08-30 02:01 UTC (permalink / raw)
To: Michael Paquier <[email protected]>; +Cc: Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers; [email protected] <[email protected]>
On Wed, Aug 30, 2023 at 08:22:27AM +0900, Michael Paquier wrote:
> On Tue, Aug 29, 2023 at 09:46:55AM -0700, Nathan Bossart wrote:
>> This was my first reaction [0]. I was concerned about renaming the
>> exported functions so close to release, so I was suggesting that we hold
>> off on that part until v17. If there isn't a concern with renaming these
>> functions in v16, I can proceed with something more like v2.
>
> Thanks for the pointer. This version is much better IMO, because it
> removes entirely the source of the confusion between the difference in
> backend ID and index ID treatments when fetching the local entries in
> the array. So I'm okay to rename these functions now, before .0 is
> released to get things in a better shape while addressing the issue
> reported.
Okay.
> +extern LocalPgBackendStatus *pgstat_get_local_beentry_by_index(int beid);
>
> Still I would to a bit more of s/beid/id/ for cases where the code
> refers to an index ID, and not a backend ID, especially for the
> internal routines.
Makes sense. I did this in v4.
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
Attachments:
[text/x-diff] v4-0001-rename-some-pgstat-functions.patch (10.1K, ../../20230830020151.GA2488217@nathanxps13/2-v4-0001-rename-some-pgstat-functions.patch)
download | inline diff:
From 3e360c1b970526079528159fe1c49be03d0b13b5 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <[email protected]>
Date: Thu, 24 Aug 2023 07:42:54 -0700
Subject: [PATCH v4 1/2] rename some pgstat functions
---
src/backend/utils/activity/backend_status.c | 28 ++++++++--------
src/backend/utils/adt/pgstatfuncs.c | 36 ++++++++++-----------
src/include/utils/backend_status.h | 4 +--
3 files changed, 34 insertions(+), 34 deletions(-)
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index 38f91a495b..a4860b10fc 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -849,8 +849,8 @@ pgstat_read_current_status(void)
/*
* The BackendStatusArray index is exactly the BackendId of the
* source backend. Note that this means localBackendStatusTable
- * is in order by backend_id. pgstat_fetch_stat_beentry() depends
- * on that.
+ * is in order by backend_id. pgstat_get_beentry_by_backend_id()
+ * depends on that.
*/
localentry->backend_id = i;
BackendIdGetTransactionIds(i,
@@ -1073,21 +1073,21 @@ cmp_lbestatus(const void *a, const void *b)
}
/* ----------
- * pgstat_fetch_stat_beentry() -
+ * pgstat_get_beentry_by_backend_id() -
*
* Support function for the SQL-callable pgstat* functions. Returns
* our local copy of the current-activity entry for one backend,
* or NULL if the given beid doesn't identify any known session.
*
* The beid argument is the BackendId of the desired session
- * (note that this is unlike pgstat_fetch_stat_local_beentry()).
+ * (note that this is unlike pgstat_get_local_beentry_by_index()).
*
* NB: caller is responsible for a check if the user is permitted to see
* this info (especially the querystring).
* ----------
*/
PgBackendStatus *
-pgstat_fetch_stat_beentry(BackendId beid)
+pgstat_get_beentry_by_backend_id(BackendId beid)
{
LocalPgBackendStatus key;
LocalPgBackendStatus *ret;
@@ -1111,13 +1111,13 @@ pgstat_fetch_stat_beentry(BackendId beid)
/* ----------
- * pgstat_fetch_stat_local_beentry() -
+ * pgstat_get_local_beentry_by_index() -
*
- * Like pgstat_fetch_stat_beentry() but with locally computed additions (like
- * xid and xmin values of the backend)
+ * Like pgstat_get_beentry_by_backend_id() but with locally computed additions
+ * (like xid and xmin values of the backend)
*
- * The beid argument is a 1-based index in the localBackendStatusTable
- * (note that this is unlike pgstat_fetch_stat_beentry()).
+ * The idx argument is a 1-based index in the localBackendStatusTable
+ * (note that this is unlike pgstat_get_beentry_by_backend_id()).
* Returns NULL if the argument is out of range (no current caller does that).
*
* NB: caller is responsible for a check if the user is permitted to see
@@ -1125,14 +1125,14 @@ pgstat_fetch_stat_beentry(BackendId beid)
* ----------
*/
LocalPgBackendStatus *
-pgstat_fetch_stat_local_beentry(int beid)
+pgstat_get_local_beentry_by_index(int idx)
{
pgstat_read_current_status();
- if (beid < 1 || beid > localNumBackends)
+ if (idx < 1 || idx > localNumBackends)
return NULL;
- return &localBackendStatusTable[beid - 1];
+ return &localBackendStatusTable[idx - 1];
}
@@ -1141,7 +1141,7 @@ pgstat_fetch_stat_local_beentry(int beid)
*
* Support function for the SQL-callable pgstat* functions. Returns
* the number of sessions known in the localBackendStatusTable, i.e.
- * the maximum 1-based index to pass to pgstat_fetch_stat_local_beentry().
+ * the maximum 1-based index to pass to pgstat_get_local_beentry_by_index().
* ----------
*/
int
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 2b9742ad21..49cc887b97 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -211,7 +211,7 @@ pg_stat_get_backend_idset(PG_FUNCTION_ARGS)
if (fctx[0] <= pgstat_fetch_stat_numbackends())
{
/* do when there is more left to send */
- LocalPgBackendStatus *local_beentry = pgstat_fetch_stat_local_beentry(fctx[0]);
+ LocalPgBackendStatus *local_beentry = pgstat_get_local_beentry_by_index(fctx[0]);
SRF_RETURN_NEXT(funcctx, Int32GetDatum(local_beentry->backend_id));
}
@@ -264,7 +264,7 @@ pg_stat_get_progress_info(PG_FUNCTION_ARGS)
bool nulls[PG_STAT_GET_PROGRESS_COLS] = {0};
int i;
- local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
+ local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
beentry = &local_beentry->backendStatus;
/*
@@ -325,7 +325,7 @@ pg_stat_get_activity(PG_FUNCTION_ARGS)
const char *wait_event = NULL;
/* Get the next one in the list */
- local_beentry = pgstat_fetch_stat_local_beentry(curr_backend);
+ local_beentry = pgstat_get_local_beentry_by_index(curr_backend);
beentry = &local_beentry->backendStatus;
/* If looking for specific PID, ignore all the others */
@@ -672,7 +672,7 @@ pg_stat_get_backend_pid(PG_FUNCTION_ARGS)
int32 beid = PG_GETARG_INT32(0);
PgBackendStatus *beentry;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
PG_RETURN_INT32(beentry->st_procpid);
@@ -685,7 +685,7 @@ pg_stat_get_backend_dbid(PG_FUNCTION_ARGS)
int32 beid = PG_GETARG_INT32(0);
PgBackendStatus *beentry;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
PG_RETURN_OID(beentry->st_databaseid);
@@ -698,7 +698,7 @@ pg_stat_get_backend_userid(PG_FUNCTION_ARGS)
int32 beid = PG_GETARG_INT32(0);
PgBackendStatus *beentry;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
PG_RETURN_OID(beentry->st_userid);
@@ -727,7 +727,7 @@ pg_stat_get_backend_subxact(PG_FUNCTION_ARGS)
BlessTupleDesc(tupdesc);
- if ((local_beentry = pgstat_fetch_stat_local_beentry(beid)) != NULL)
+ if ((local_beentry = pgstat_get_local_beentry_by_index(beid)) != NULL)
{
/* Fill values and NULLs */
values[0] = Int32GetDatum(local_beentry->backend_subxact_count);
@@ -752,7 +752,7 @@ pg_stat_get_backend_activity(PG_FUNCTION_ARGS)
char *clipped_activity;
text *ret;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
activity = "<backend information not available>";
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
activity = "<insufficient privilege>";
@@ -776,7 +776,7 @@ pg_stat_get_backend_wait_event_type(PG_FUNCTION_ARGS)
PGPROC *proc;
const char *wait_event_type = NULL;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
wait_event_type = "<backend information not available>";
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
wait_event_type = "<insufficient privilege>";
@@ -797,7 +797,7 @@ pg_stat_get_backend_wait_event(PG_FUNCTION_ARGS)
PGPROC *proc;
const char *wait_event = NULL;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
wait_event = "<backend information not available>";
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
wait_event = "<insufficient privilege>";
@@ -818,7 +818,7 @@ pg_stat_get_backend_activity_start(PG_FUNCTION_ARGS)
TimestampTz result;
PgBackendStatus *beentry;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@@ -844,7 +844,7 @@ pg_stat_get_backend_xact_start(PG_FUNCTION_ARGS)
TimestampTz result;
PgBackendStatus *beentry;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@@ -866,7 +866,7 @@ pg_stat_get_backend_start(PG_FUNCTION_ARGS)
TimestampTz result;
PgBackendStatus *beentry;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@@ -890,7 +890,7 @@ pg_stat_get_backend_client_addr(PG_FUNCTION_ARGS)
char remote_host[NI_MAXHOST];
int ret;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@@ -935,7 +935,7 @@ pg_stat_get_backend_client_port(PG_FUNCTION_ARGS)
char remote_port[NI_MAXSERV];
int ret;
- if ((beentry = pgstat_fetch_stat_beentry(beid)) == NULL)
+ if ((beentry = pgstat_get_beentry_by_backend_id(beid)) == NULL)
PG_RETURN_NULL();
else if (!HAS_PGSTAT_PERMISSIONS(beentry->st_userid))
@@ -978,12 +978,12 @@ pg_stat_get_db_numbackends(PG_FUNCTION_ARGS)
Oid dbid = PG_GETARG_OID(0);
int32 result;
int tot_backends = pgstat_fetch_stat_numbackends();
- int beid;
+ int idx;
result = 0;
- for (beid = 1; beid <= tot_backends; beid++)
+ for (idx = 1; idx <= tot_backends; idx++)
{
- LocalPgBackendStatus *local_beentry = pgstat_fetch_stat_local_beentry(beid);
+ LocalPgBackendStatus *local_beentry = pgstat_get_local_beentry_by_index(idx);
if (local_beentry->backendStatus.st_databaseid == dbid)
result++;
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 77939a0aed..1718ff7ce6 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -333,8 +333,8 @@ extern uint64 pgstat_get_my_query_id(void);
* ----------
*/
extern int pgstat_fetch_stat_numbackends(void);
-extern PgBackendStatus *pgstat_fetch_stat_beentry(BackendId beid);
-extern LocalPgBackendStatus *pgstat_fetch_stat_local_beentry(int beid);
+extern PgBackendStatus *pgstat_get_beentry_by_backend_id(BackendId beid);
+extern LocalPgBackendStatus *pgstat_get_local_beentry_by_index(int idx);
extern char *pgstat_clip_activity(const char *raw_activity);
--
2.25.1
[text/x-diff] v4-0002-fix-pg_stat_get_backend_subxact-to-use-real-backe.patch (3.3K, ../../20230830020151.GA2488217@nathanxps13/3-v4-0002-fix-pg_stat_get_backend_subxact-to-use-real-backe.patch)
download | inline diff:
From dc162a99a94e7c5483bfb77c40dac877e0ed5682 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <[email protected]>
Date: Thu, 24 Aug 2023 07:58:01 -0700
Subject: [PATCH v4 2/2] fix pg_stat_get_backend_subxact to use real backend id
---
src/backend/utils/activity/backend_status.c | 36 +++++++++++++++------
src/backend/utils/adt/pgstatfuncs.c | 2 +-
src/include/utils/backend_status.h | 1 +
3 files changed, 29 insertions(+), 10 deletions(-)
diff --git a/src/backend/utils/activity/backend_status.c b/src/backend/utils/activity/backend_status.c
index a4860b10fc..722c5acf38 100644
--- a/src/backend/utils/activity/backend_status.c
+++ b/src/backend/utils/activity/backend_status.c
@@ -1088,9 +1088,33 @@ cmp_lbestatus(const void *a, const void *b)
*/
PgBackendStatus *
pgstat_get_beentry_by_backend_id(BackendId beid)
+{
+ LocalPgBackendStatus *ret = pgstat_get_local_beentry_by_backend_id(beid);
+
+ if (ret)
+ return &ret->backendStatus;
+
+ return NULL;
+}
+
+
+/* ----------
+ * pgstat_get_local_beentry_by_backend_id() -
+ *
+ * Like pgstat_get_beentry_by_backend_id() but with locally computed additions
+ * (like xid and xmin values of the backend)
+ *
+ * The beid argument is the BackendId of the desired session
+ * (note that this is unlike pgstat_get_local_beentry_by_index()).
+ *
+ * NB: caller is responsible for checking if the user is permitted to see this
+ * info (especially the querystring).
+ * ----------
+ */
+LocalPgBackendStatus *
+pgstat_get_local_beentry_by_backend_id(BackendId beid)
{
LocalPgBackendStatus key;
- LocalPgBackendStatus *ret;
pgstat_read_current_status();
@@ -1099,14 +1123,8 @@ pgstat_get_beentry_by_backend_id(BackendId beid)
* bsearch() to search it efficiently.
*/
key.backend_id = beid;
- ret = (LocalPgBackendStatus *) bsearch(&key, localBackendStatusTable,
- localNumBackends,
- sizeof(LocalPgBackendStatus),
- cmp_lbestatus);
- if (ret)
- return &ret->backendStatus;
-
- return NULL;
+ return bsearch(&key, localBackendStatusTable, localNumBackends,
+ sizeof(LocalPgBackendStatus), cmp_lbestatus);
}
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 49cc887b97..dd5094a2d4 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -727,7 +727,7 @@ pg_stat_get_backend_subxact(PG_FUNCTION_ARGS)
BlessTupleDesc(tupdesc);
- if ((local_beentry = pgstat_get_local_beentry_by_index(beid)) != NULL)
+ if ((local_beentry = pgstat_get_local_beentry_by_backend_id(beid)) != NULL)
{
/* Fill values and NULLs */
values[0] = Int32GetDatum(local_beentry->backend_subxact_count);
diff --git a/src/include/utils/backend_status.h b/src/include/utils/backend_status.h
index 1718ff7ce6..d51c840daf 100644
--- a/src/include/utils/backend_status.h
+++ b/src/include/utils/backend_status.h
@@ -334,6 +334,7 @@ extern uint64 pgstat_get_my_query_id(void);
*/
extern int pgstat_fetch_stat_numbackends(void);
extern PgBackendStatus *pgstat_get_beentry_by_backend_id(BackendId beid);
+extern LocalPgBackendStatus *pgstat_get_local_beentry_by_backend_id(BackendId beid);
extern LocalPgBackendStatus *pgstat_get_local_beentry_by_index(int idx);
extern char *pgstat_clip_activity(const char *raw_activity);
--
2.25.1
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-30 04:13 Michael Paquier <[email protected]>
parent: Nathan Bossart <[email protected]>
0 siblings, 1 reply; 12+ messages in thread
From: Michael Paquier @ 2023-08-30 04:13 UTC (permalink / raw)
To: Nathan Bossart <[email protected]>; +Cc: Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers; [email protected] <[email protected]>
On Tue, Aug 29, 2023 at 07:01:51PM -0700, Nathan Bossart wrote:
> On Wed, Aug 30, 2023 at 08:22:27AM +0900, Michael Paquier wrote:
>> +extern LocalPgBackendStatus *pgstat_get_local_beentry_by_index(int beid);
>>
>> Still I would to a bit more of s/beid/id/ for cases where the code
>> refers to an index ID, and not a backend ID, especially for the
>> internal routines.
>
> Makes sense. I did this in v4.
Yep, that looks more consistent, at quick glance.
--
Michael
Attachments:
[application/pgp-signature] signature.asc (833B, ../../[email protected]/2-signature.asc)
download
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-30 13:50 Robert Haas <[email protected]>
parent: Michael Paquier <[email protected]>
0 siblings, 1 reply; 12+ messages in thread
From: Robert Haas @ 2023-08-30 13:50 UTC (permalink / raw)
To: Michael Paquier <[email protected]>; +Cc: Nathan Bossart <[email protected]>; Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers
On Wed, Aug 30, 2023 at 12:13 AM Michael Paquier <[email protected]> wrote:
> Yep, that looks more consistent, at quick glance.
Sorry, I'm only just noticing this thread. Thanks, Nathan, Ian, and
others, for your work on this. Apart from hoping that the 0002 patch
will get a more detailed commit message spelling out the problem very
explicitly, I don't have any comments on the proposed patches.
--
Robert Haas
EDB: http://www.enterprisedb.com
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-30 14:27 Nathan Bossart <[email protected]>
parent: Robert Haas <[email protected]>
0 siblings, 1 reply; 12+ messages in thread
From: Nathan Bossart @ 2023-08-30 14:27 UTC (permalink / raw)
To: Robert Haas <[email protected]>; +Cc: Michael Paquier <[email protected]>; Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers
On Wed, Aug 30, 2023 at 09:50:41AM -0400, Robert Haas wrote:
> Sorry, I'm only just noticing this thread. Thanks, Nathan, Ian, and
> others, for your work on this. Apart from hoping that the 0002 patch
> will get a more detailed commit message spelling out the problem very
> explicitly, I don't have any comments on the proposed patches.
I'm about to spend way too much time writing the commit message for 0002,
but I plan to commit both patches sometime today.
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-30 14:56 Robert Haas <[email protected]>
parent: Nathan Bossart <[email protected]>
0 siblings, 1 reply; 12+ messages in thread
From: Robert Haas @ 2023-08-30 14:56 UTC (permalink / raw)
To: Nathan Bossart <[email protected]>; +Cc: Michael Paquier <[email protected]>; Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers
On Wed, Aug 30, 2023 at 10:27 AM Nathan Bossart
<[email protected]> wrote:
> On Wed, Aug 30, 2023 at 09:50:41AM -0400, Robert Haas wrote:
> > Sorry, I'm only just noticing this thread. Thanks, Nathan, Ian, and
> > others, for your work on this. Apart from hoping that the 0002 patch
> > will get a more detailed commit message spelling out the problem very
> > explicitly, I don't have any comments on the proposed patches.
>
> I'm about to spend way too much time writing the commit message for 0002,
> but I plan to commit both patches sometime today.
Thanks! I'm glad your committing the patches, and I approve of you
spending way too much time on the commit message. :-)
--
Robert Haas
EDB: http://www.enterprisedb.com
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-30 21:56 Nathan Bossart <[email protected]>
parent: Robert Haas <[email protected]>
0 siblings, 3 replies; 12+ messages in thread
From: Nathan Bossart @ 2023-08-30 21:56 UTC (permalink / raw)
To: Robert Haas <[email protected]>; +Cc: Michael Paquier <[email protected]>; Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers
On Wed, Aug 30, 2023 at 10:56:22AM -0400, Robert Haas wrote:
> On Wed, Aug 30, 2023 at 10:27 AM Nathan Bossart
> <[email protected]> wrote:
>> I'm about to spend way too much time writing the commit message for 0002,
>> but I plan to commit both patches sometime today.
>
> Thanks! I'm glad your committing the patches, and I approve of you
> spending way too much time on the commit message. :-)
Committed.
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-31 04:22 Michael Paquier <[email protected]>
parent: Nathan Bossart <[email protected]>
2 siblings, 0 replies; 12+ messages in thread
From: Michael Paquier @ 2023-08-31 04:22 UTC (permalink / raw)
To: Nathan Bossart <[email protected]>; +Cc: Robert Haas <[email protected]>; Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers
On Wed, Aug 30, 2023 at 02:56:48PM -0700, Nathan Bossart wrote:
> Committed.
Cool, thanks!
--
Michael
Attachments:
[application/pgp-signature] signature.asc (833B, ../../[email protected]/2-signature.asc)
download
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-08-31 11:17 Dilip Kumar <[email protected]>
parent: Nathan Bossart <[email protected]>
2 siblings, 0 replies; 12+ messages in thread
From: Dilip Kumar @ 2023-08-31 11:17 UTC (permalink / raw)
To: Nathan Bossart <[email protected]>; +Cc: Robert Haas <[email protected]>; Michael Paquier <[email protected]>; Imseih (AWS), Sami <[email protected]>; Ian Lawrence Barwick <[email protected]>; pgsql-hackers
On Thu, Aug 31, 2023 at 4:38 AM Nathan Bossart <[email protected]> wrote:
>
> On Wed, Aug 30, 2023 at 10:56:22AM -0400, Robert Haas wrote:
> > On Wed, Aug 30, 2023 at 10:27 AM Nathan Bossart
> > <[email protected]> wrote:
> >> I'm about to spend way too much time writing the commit message for 0002,
> >> but I plan to commit both patches sometime today.
> >
> > Thanks! I'm glad your committing the patches, and I approve of you
> > spending way too much time on the commit message. :-)
>
> Committed.
Sorry, I didn't notice this thread earlier. The new behavior looks
better to me, thanks for working on it.
--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com
^ permalink raw reply [nested|flat] 12+ messages in thread
* Re: pg_stat_get_backend_subxact() and backend IDs?
@ 2023-09-18 06:52 Ian Lawrence Barwick <[email protected]>
parent: Nathan Bossart <[email protected]>
2 siblings, 0 replies; 12+ messages in thread
From: Ian Lawrence Barwick @ 2023-09-18 06:52 UTC (permalink / raw)
To: Nathan Bossart <[email protected]>; +Cc: Robert Haas <[email protected]>; Michael Paquier <[email protected]>; Imseih (AWS), Sami <[email protected]>; pgsql-hackers
2023年8月31日(木) 6:56 Nathan Bossart <[email protected]>:
>
> On Wed, Aug 30, 2023 at 10:56:22AM -0400, Robert Haas wrote:
> > On Wed, Aug 30, 2023 at 10:27 AM Nathan Bossart
> > <[email protected]> wrote:
> >> I'm about to spend way too much time writing the commit message for 0002,
> >> but I plan to commit both patches sometime today.
> >
> > Thanks! I'm glad your committing the patches, and I approve of you
> > spending way too much time on the commit message. :-)
>
> Committed.
Thanks for taking care of this (saw the commits, then got distracted
by something else and forgot to follow up).
Regards
Ian Barwick
^ permalink raw reply [nested|flat] 12+ messages in thread
* [PATCH v22 5/8] Row pattern recognition patch (executor).
@ 2024-09-19 04:48 Tatsuo Ishii <[email protected]>
0 siblings, 0 replies; 12+ messages in thread
From: Tatsuo Ishii @ 2024-09-19 04:48 UTC (permalink / raw)
---
src/backend/executor/nodeWindowAgg.c | 1610 +++++++++++++++++++++++++-
src/backend/utils/adt/windowfuncs.c | 37 +-
src/include/catalog/pg_proc.dat | 6 +
src/include/nodes/execnodes.h | 30 +
4 files changed, 1671 insertions(+), 12 deletions(-)
diff --git a/src/backend/executor/nodeWindowAgg.c b/src/backend/executor/nodeWindowAgg.c
index 51a6708a39..e46a3dd1b7 100644
--- a/src/backend/executor/nodeWindowAgg.c
+++ b/src/backend/executor/nodeWindowAgg.c
@@ -36,6 +36,7 @@
#include "access/htup_details.h"
#include "catalog/objectaccess.h"
#include "catalog/pg_aggregate.h"
+#include "catalog/pg_collation_d.h"
#include "catalog/pg_proc.h"
#include "executor/executor.h"
#include "executor/nodeWindowAgg.h"
@@ -48,6 +49,7 @@
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/datum.h"
+#include "utils/fmgroids.h"
#include "utils/expandeddatum.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
@@ -159,6 +161,43 @@ typedef struct WindowStatePerAggData
bool restart; /* need to restart this agg in this cycle? */
} WindowStatePerAggData;
+/*
+ * Set of StringInfo. Used in RPR.
+ */
+typedef struct StringSet
+{
+ StringInfo *str_set;
+ Size set_size; /* current array allocation size in number of
+ * items */
+ int set_index; /* current used size */
+} StringSet;
+
+/*
+ * Allowed subsequent PATTERN variables positions.
+ * Used in RPR.
+ *
+ * pos represents the pattern variable defined order in DEFINE caluase. For
+ * example. "DEFINE START..., UP..., DOWN ..." and "PATTERN START UP DOWN UP"
+ * will create:
+ * VariablePos[0].pos[0] = 0; START
+ * VariablePos[1].pos[0] = 1; UP
+ * VariablePos[1].pos[1] = 3; UP
+ * VariablePos[2].pos[0] = 2; DOWN
+ *
+ * Note that UP has two pos because UP appears in PATTERN twice.
+ *
+ * By using this strucrture, we can know which pattern variable can be followed
+ * by which pattern variable(s). For example, START can be followed by UP and
+ * DOWN since START's pos is 0, and UP's pos is 1 or 3, DOWN's pos is 2.
+ * DOWN can be followed by UP since UP's pos is either 1 or 3.
+ *
+ */
+#define NUM_ALPHABETS 26 /* we allow [a-z] variable initials */
+typedef struct VariablePos
+{
+ int pos[NUM_ALPHABETS]; /* postion(s) in PATTERN */
+} VariablePos;
+
static void initialize_windowaggregate(WindowAggState *winstate,
WindowStatePerFunc perfuncstate,
WindowStatePerAgg peraggstate);
@@ -184,6 +223,7 @@ static void release_partition(WindowAggState *winstate);
static int row_is_in_frame(WindowAggState *winstate, int64 pos,
TupleTableSlot *slot);
+
static void update_frameheadpos(WindowAggState *winstate);
static void update_frametailpos(WindowAggState *winstate);
static void update_grouptailpos(WindowAggState *winstate);
@@ -195,9 +235,48 @@ static Datum GetAggInitVal(Datum textInitVal, Oid transtype);
static bool are_peers(WindowAggState *winstate, TupleTableSlot *slot1,
TupleTableSlot *slot2);
+
+static int WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot,
+ int relpos, int seektype, bool set_mark,
+ bool *isnull, bool *isout);
static bool window_gettupleslot(WindowObject winobj, int64 pos,
TupleTableSlot *slot);
+static void attno_map(Node *node);
+static bool attno_map_walker(Node *node, void *context);
+static int row_is_in_reduced_frame(WindowObject winobj, int64 pos);
+static bool rpr_is_defined(WindowAggState *winstate);
+
+static void create_reduced_frame_map(WindowAggState *winstate);
+static int get_reduced_frame_map(WindowAggState *winstate, int64 pos);
+static void register_reduced_frame_map(WindowAggState *winstate, int64 pos,
+ int val);
+static void clear_reduced_frame_map(WindowAggState *winstate);
+static void update_reduced_frame(WindowObject winobj, int64 pos);
+
+static int64 evaluate_pattern(WindowObject winobj, int64 current_pos,
+ char *vname, StringInfo encoded_str, bool *result);
+
+static bool get_slots(WindowObject winobj, int64 current_pos);
+
+static int search_str_set(char *pattern, StringSet * str_set,
+ VariablePos * variable_pos);
+static char pattern_initial(WindowAggState *winstate, char *vname);
+static int do_pattern_match(char *pattern, char *encoded_str);
+
+static StringSet * string_set_init(void);
+static void string_set_add(StringSet * string_set, StringInfo str);
+static StringInfo string_set_get(StringSet * string_set, int index);
+static int string_set_get_size(StringSet * string_set);
+static void string_set_discard(StringSet * string_set);
+static VariablePos * variable_pos_init(void);
+static void variable_pos_register(VariablePos * variable_pos, char initial,
+ int pos);
+static bool variable_pos_compare(VariablePos * variable_pos,
+ char initial1, char initial2);
+static int variable_pos_fetch(VariablePos * variable_pos, char initial,
+ int index);
+static void variable_pos_discard(VariablePos * variable_pos);
/*
* initialize_windowaggregate
@@ -774,10 +853,12 @@ eval_windowaggregates(WindowAggState *winstate)
* transition function, or
* - we have an EXCLUSION clause, or
* - if the new frame doesn't overlap the old one
+ * - if RPR is enabled
*
* Note that we don't strictly need to restart in the last case, but if
* we're going to remove all rows from the aggregation anyway, a restart
* surely is faster.
+ * we restart aggregation too.
*----------
*/
numaggs_restart = 0;
@@ -788,7 +869,8 @@ eval_windowaggregates(WindowAggState *winstate)
(winstate->aggregatedbase != winstate->frameheadpos &&
!OidIsValid(peraggstate->invtransfn_oid)) ||
(winstate->frameOptions & FRAMEOPTION_EXCLUSION) ||
- winstate->aggregatedupto <= winstate->frameheadpos)
+ winstate->aggregatedupto <= winstate->frameheadpos ||
+ rpr_is_defined(winstate))
{
peraggstate->restart = true;
numaggs_restart++;
@@ -862,7 +944,22 @@ eval_windowaggregates(WindowAggState *winstate)
* head, so that tuplestore can discard unnecessary rows.
*/
if (agg_winobj->markptr >= 0)
- WinSetMarkPosition(agg_winobj, winstate->frameheadpos);
+ {
+ int64 markpos = winstate->frameheadpos;
+
+ if (rpr_is_defined(winstate))
+ {
+ /*
+ * If RPR is used, it is possible PREV wants to look at the
+ * previous row. So the mark pos should be frameheadpos - 1
+ * unless it is below 0.
+ */
+ markpos -= 1;
+ if (markpos < 0)
+ markpos = 0;
+ }
+ WinSetMarkPosition(agg_winobj, markpos);
+ }
/*
* Now restart the aggregates that require it.
@@ -917,6 +1014,14 @@ eval_windowaggregates(WindowAggState *winstate)
{
winstate->aggregatedupto = winstate->frameheadpos;
ExecClearTuple(agg_row_slot);
+
+ /*
+ * If RPR is defined, we do not use aggregatedupto_nonrestarted. To
+ * avoid assertion failure below, we reset aggregatedupto_nonrestarted
+ * to frameheadpos.
+ */
+ if (rpr_is_defined(winstate))
+ aggregatedupto_nonrestarted = winstate->frameheadpos;
}
/*
@@ -930,6 +1035,12 @@ eval_windowaggregates(WindowAggState *winstate)
{
int ret;
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "===== loop in frame starts: aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT,
+ winstate->aggregatedupto,
+ winstate->aggregatedbase);
+#endif
+
/* Fetch next row if we didn't already */
if (TupIsNull(agg_row_slot))
{
@@ -945,9 +1056,52 @@ eval_windowaggregates(WindowAggState *winstate)
ret = row_is_in_frame(winstate, winstate->aggregatedupto, agg_row_slot);
if (ret < 0)
break;
+
if (ret == 0)
goto next_tuple;
+ if (rpr_is_defined(winstate))
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "reduced_frame_map: %d aggregatedupto: " INT64_FORMAT " aggregatedbase: " INT64_FORMAT,
+ get_reduced_frame_map(winstate,
+ winstate->aggregatedupto),
+ winstate->aggregatedupto,
+ winstate->aggregatedbase);
+#endif
+ /*
+ * If the row status at currentpos is already decided and current
+ * row status is not decided yet, it means we passed the last
+ * reduced frame. Time to break the loop.
+ */
+ if (get_reduced_frame_map(winstate,
+ winstate->currentpos) != RF_NOT_DETERMINED &&
+ get_reduced_frame_map(winstate,
+ winstate->aggregatedupto) == RF_NOT_DETERMINED)
+ break;
+
+ /*
+ * Otherwise we need to calculate the reduced frame.
+ */
+ ret = row_is_in_reduced_frame(winstate->agg_winobj,
+ winstate->aggregatedupto);
+ if (ret == -1) /* unmatched row */
+ break;
+
+ /*
+ * Check if current row needs to be skipped due to no match.
+ */
+ if (get_reduced_frame_map(winstate,
+ winstate->aggregatedupto) == RF_SKIPPED &&
+ winstate->aggregatedupto == winstate->aggregatedbase)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "skip current row for aggregation");
+#endif
+ break;
+ }
+ }
+
/* Set tuple context for evaluation of aggregate arguments */
winstate->tmpcontext->ecxt_outertuple = agg_row_slot;
@@ -976,6 +1130,7 @@ next_tuple:
ExecClearTuple(agg_row_slot);
}
+
/* The frame's end is not supposed to move backwards, ever */
Assert(aggregatedupto_nonrestarted <= winstate->aggregatedupto);
@@ -995,7 +1150,6 @@ next_tuple:
&winstate->perfunc[wfuncno],
peraggstate,
result, isnull);
-
/*
* save the result in case next row shares the same frame.
*
@@ -1199,6 +1353,7 @@ begin_partition(WindowAggState *winstate)
winstate->framehead_valid = false;
winstate->frametail_valid = false;
winstate->grouptail_valid = false;
+ create_reduced_frame_map(winstate);
winstate->spooled_rows = 0;
winstate->currentpos = 0;
winstate->frameheadpos = 0;
@@ -2170,6 +2325,11 @@ ExecWindowAgg(PlanState *pstate)
CHECK_FOR_INTERRUPTS();
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "ExecWindowAgg called. pos: " INT64_FORMAT,
+ winstate->currentpos);
+#endif
+
if (winstate->status == WINDOWAGG_DONE)
return NULL;
@@ -2278,6 +2438,17 @@ ExecWindowAgg(PlanState *pstate)
/* don't evaluate the window functions when we're in pass-through mode */
if (winstate->status == WINDOWAGG_RUN)
{
+ /*
+ * If RPR is defined and skip mode is next row, we need to clear
+ * existing reduced frame info so that we newly calculate the info
+ * starting from current row.
+ */
+ if (rpr_is_defined(winstate))
+ {
+ if (winstate->rpSkipTo == ST_NEXT_ROW)
+ clear_reduced_frame_map(winstate);
+ }
+
/*
* Evaluate true window functions
*/
@@ -2445,6 +2616,9 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags)
TupleDesc scanDesc;
ListCell *l;
+ TargetEntry *te;
+ Expr *expr;
+
/* check for unsupported flags */
Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
@@ -2543,6 +2717,16 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags)
winstate->temp_slot_2 = ExecInitExtraTupleSlot(estate, scanDesc,
&TTSOpsMinimalTuple);
+ winstate->prev_slot = ExecInitExtraTupleSlot(estate, scanDesc,
+ &TTSOpsMinimalTuple);
+
+ winstate->next_slot = ExecInitExtraTupleSlot(estate, scanDesc,
+ &TTSOpsMinimalTuple);
+
+ winstate->null_slot = ExecInitExtraTupleSlot(estate, scanDesc,
+ &TTSOpsMinimalTuple);
+ winstate->null_slot = ExecStoreAllNullTuple(winstate->null_slot);
+
/*
* create frame head and tail slots only if needed (must create slots in
* exactly the same cases that update_frameheadpos and update_frametailpos
@@ -2724,6 +2908,43 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags)
winstate->inRangeAsc = node->inRangeAsc;
winstate->inRangeNullsFirst = node->inRangeNullsFirst;
+ /* Set up SKIP TO type */
+ winstate->rpSkipTo = node->rpSkipTo;
+ /* Set up row pattern recognition PATTERN clause */
+ winstate->patternVariableList = node->patternVariable;
+ winstate->patternRegexpList = node->patternRegexp;
+
+ /* Set up row pattern recognition DEFINE clause */
+ winstate->defineInitial = node->defineInitial;
+ winstate->defineVariableList = NIL;
+ winstate->defineClauseList = NIL;
+ if (node->defineClause != NIL)
+ {
+ /*
+ * Tweak arg var of PREV/NEXT so that it refers to scan/inner slot.
+ */
+ foreach(l, node->defineClause)
+ {
+ char *name;
+ ExprState *exps;
+
+ te = lfirst(l);
+ name = te->resname;
+ expr = te->expr;
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "defineVariable name: %s", name);
+#endif
+ winstate->defineVariableList =
+ lappend(winstate->defineVariableList,
+ makeString(pstrdup(name)));
+ attno_map((Node *) expr);
+ exps = ExecInitExpr(expr, (PlanState *) winstate);
+ winstate->defineClauseList =
+ lappend(winstate->defineClauseList, exps);
+ }
+ }
+
winstate->all_first = true;
winstate->partition_spooled = false;
winstate->more_partitions = false;
@@ -2732,6 +2953,64 @@ ExecInitWindowAgg(WindowAgg *node, EState *estate, int eflags)
return winstate;
}
+/*
+ * Rewrite varno of Var node that is the argument of PREV/NET so that it sees
+ * scan tuple (PREV) or inner tuple (NEXT).
+ */
+static void
+attno_map(Node *node)
+{
+ (void) expression_tree_walker(node, attno_map_walker, NULL);
+}
+
+static bool
+attno_map_walker(Node *node, void *context)
+{
+ FuncExpr *func;
+ int nargs;
+ Expr *expr;
+ Var *var;
+
+ if (node == NULL)
+ return false;
+
+ if (IsA(node, FuncExpr))
+ {
+ func = (FuncExpr *) node;
+
+ if (func->funcid == F_PREV || func->funcid == F_NEXT)
+ {
+ /* sanity check */
+ nargs = list_length(func->args);
+ if (list_length(func->args) != 1)
+ elog(ERROR, "PREV/NEXT must have 1 argument but function %d has %d args",
+ func->funcid, nargs);
+
+ expr = (Expr *) lfirst(list_head(func->args));
+ if (!IsA(expr, Var))
+ elog(ERROR, "PREV/NEXT's arg is not Var"); /* XXX: is it possible
+ * that arg type is
+ * Const? */
+ var = (Var *) expr;
+
+ if (func->funcid == F_PREV)
+
+ /*
+ * Rewrite varno from OUTER_VAR to regular var no so that the
+ * var references scan tuple.
+ */
+ var->varno = var->varnosyn;
+ else
+ var->varno = INNER_VAR;
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "PREV/NEXT's varno is rewritten to: %d", var->varno);
+#endif
+ }
+ }
+ return expression_tree_walker(node, attno_map_walker, NULL);
+}
+
/* -----------------
* ExecEndWindowAgg
* -----------------
@@ -2789,6 +3068,8 @@ ExecReScanWindowAgg(WindowAggState *node)
ExecClearTuple(node->agg_row_slot);
ExecClearTuple(node->temp_slot_1);
ExecClearTuple(node->temp_slot_2);
+ ExecClearTuple(node->prev_slot);
+ ExecClearTuple(node->next_slot);
if (node->framehead_slot)
ExecClearTuple(node->framehead_slot);
if (node->frametail_slot)
@@ -3149,7 +3430,8 @@ window_gettupleslot(WindowObject winobj, int64 pos, TupleTableSlot *slot)
return false;
if (pos < winobj->markpos)
- elog(ERROR, "cannot fetch row before WindowObject's mark position");
+ elog(ERROR, "cannot fetch row: " INT64_FORMAT " before WindowObject's mark position: " INT64_FORMAT,
+ pos, winobj->markpos);
oldcontext = MemoryContextSwitchTo(winstate->ss.ps.ps_ExprContext->ecxt_per_query_memory);
@@ -3469,14 +3751,54 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno,
WindowAggState *winstate;
ExprContext *econtext;
TupleTableSlot *slot;
- int64 abs_pos;
- int64 mark_pos;
Assert(WindowObjectIsValid(winobj));
winstate = winobj->winstate;
econtext = winstate->ss.ps.ps_ExprContext;
slot = winstate->temp_slot_1;
+ if (WinGetSlotInFrame(winobj, slot,
+ relpos, seektype, set_mark,
+ isnull, isout) == 0)
+ {
+ econtext->ecxt_outertuple = slot;
+ return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno),
+ econtext, isnull);
+ }
+
+ if (isout)
+ *isout = true;
+ *isnull = true;
+ return (Datum) 0;
+}
+
+/*
+ * WinGetSlotInFrame
+ * slot: TupleTableSlot to store the result
+ * relpos: signed rowcount offset from the seek position
+ * seektype: WINDOW_SEEK_HEAD or WINDOW_SEEK_TAIL
+ * set_mark: If the row is found/in frame and set_mark is true, the mark is
+ * moved to the row as a side-effect.
+ * isnull: output argument, receives isnull status of result
+ * isout: output argument, set to indicate whether target row position
+ * is out of frame (can pass NULL if caller doesn't care about this)
+ *
+ * Returns 0 if we successfullt got the slot. false if out of frame.
+ * (also isout is set)
+ */
+static int
+WinGetSlotInFrame(WindowObject winobj, TupleTableSlot *slot,
+ int relpos, int seektype, bool set_mark,
+ bool *isnull, bool *isout)
+{
+ WindowAggState *winstate;
+ int64 abs_pos;
+ int64 mark_pos;
+ int num_reduced_frame;
+
+ Assert(WindowObjectIsValid(winobj));
+ winstate = winobj->winstate;
+
switch (seektype)
{
case WINDOW_SEEK_CURRENT:
@@ -3543,11 +3865,25 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno,
winstate->frameOptions);
break;
}
+ num_reduced_frame = row_is_in_reduced_frame(winobj,
+ winstate->frameheadpos);
+ if (num_reduced_frame < 0)
+ goto out_of_frame;
+ else if (num_reduced_frame > 0)
+ if (relpos >= num_reduced_frame)
+ goto out_of_frame;
break;
case WINDOW_SEEK_TAIL:
/* rejecting relpos > 0 is easy and simplifies code below */
if (relpos > 0)
goto out_of_frame;
+
+ /*
+ * RPR cares about frame head pos. Need to call
+ * update_frameheadpos
+ */
+ update_frameheadpos(winstate);
+
update_frametailpos(winstate);
abs_pos = winstate->frametailpos - 1 + relpos;
@@ -3614,6 +3950,14 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno,
mark_pos = 0; /* keep compiler quiet */
break;
}
+
+ num_reduced_frame = row_is_in_reduced_frame(winobj,
+ winstate->frameheadpos + relpos);
+ if (num_reduced_frame < 0)
+ goto out_of_frame;
+ else if (num_reduced_frame > 0)
+ abs_pos = winstate->frameheadpos + relpos +
+ num_reduced_frame - 1;
break;
default:
elog(ERROR, "unrecognized window seek type: %d", seektype);
@@ -3632,15 +3976,13 @@ WinGetFuncArgInFrame(WindowObject winobj, int argno,
*isout = false;
if (set_mark)
WinSetMarkPosition(winobj, mark_pos);
- econtext->ecxt_outertuple = slot;
- return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno),
- econtext, isnull);
+ return 0;
out_of_frame:
if (isout)
*isout = true;
*isnull = true;
- return (Datum) 0;
+ return -1;
}
/*
@@ -3671,3 +4013,1251 @@ WinGetFuncArgCurrent(WindowObject winobj, int argno, bool *isnull)
return ExecEvalExpr((ExprState *) list_nth(winobj->argstates, argno),
econtext, isnull);
}
+
+/*
+ * rpr_is_defined
+ * return true if Row pattern recognition is defined.
+ */
+static
+bool
+rpr_is_defined(WindowAggState *winstate)
+{
+ return winstate->patternVariableList != NIL;
+}
+
+/*
+ * -----------------
+ * row_is_in_reduced_frame
+ * Determine whether a row is in the current row's reduced window frame
+ * according to row pattern matching
+ *
+ * The row must has been already determined that it is in a full window frame
+ * and fetched it into slot.
+ *
+ * Returns:
+ * = 0, RPR is not defined.
+ * >0, if the row is the first in the reduced frame. Return the number of rows
+ * in the reduced frame.
+ * -1, if the row is unmatched row
+ * -2, if the row is in the reduced frame but needed to be skipped because of
+ * AFTER MATCH SKIP PAST LAST ROW
+ * -----------------
+ */
+static
+int
+row_is_in_reduced_frame(WindowObject winobj, int64 pos)
+{
+ WindowAggState *winstate = winobj->winstate;
+ int state;
+ int rtn;
+
+ if (!rpr_is_defined(winstate))
+ {
+ /*
+ * RPR is not defined. Assume that we are always in the the reduced
+ * window frame.
+ */
+ rtn = 0;
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT,
+ rtn, pos);
+#endif
+ return rtn;
+ }
+
+ state = get_reduced_frame_map(winstate, pos);
+
+ if (state == RF_NOT_DETERMINED)
+ {
+ update_frameheadpos(winstate);
+ update_reduced_frame(winobj, pos);
+ }
+
+ state = get_reduced_frame_map(winstate, pos);
+
+ switch (state)
+ {
+ int64 i;
+ int num_reduced_rows;
+
+ case RF_FRAME_HEAD:
+ num_reduced_rows = 1;
+ for (i = pos + 1;
+ get_reduced_frame_map(winstate, i) == RF_SKIPPED; i++)
+ num_reduced_rows++;
+ rtn = num_reduced_rows;
+ break;
+
+ case RF_SKIPPED:
+ rtn = -2;
+ break;
+
+ case RF_UNMATCHED:
+ rtn = -1;
+ break;
+
+ default:
+ elog(ERROR, "Unrecognized state: %d at: " INT64_FORMAT,
+ state, pos);
+ break;
+ }
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "row_is_in_reduced_frame returns %d: pos: " INT64_FORMAT,
+ rtn, pos);
+#endif
+ return rtn;
+}
+
+#define REDUCED_FRAME_MAP_INIT_SIZE 1024L
+
+/*
+ * create_reduced_frame_map
+ * Create reduced frame map
+ */
+static
+void
+create_reduced_frame_map(WindowAggState *winstate)
+{
+ winstate->reduced_frame_map =
+ MemoryContextAlloc(winstate->partcontext,
+ REDUCED_FRAME_MAP_INIT_SIZE);
+ winstate->alloc_sz = REDUCED_FRAME_MAP_INIT_SIZE;
+ clear_reduced_frame_map(winstate);
+}
+
+/*
+ * clear_reduced_frame_map
+ * Clear reduced frame map
+ */
+static
+void
+clear_reduced_frame_map(WindowAggState *winstate)
+{
+ Assert(winstate->reduced_frame_map != NULL);
+ MemSet(winstate->reduced_frame_map, RF_NOT_DETERMINED,
+ winstate->alloc_sz);
+}
+
+/*
+ * get_reduced_frame_map
+ * Get reduced frame map specified by pos
+ */
+static
+int
+get_reduced_frame_map(WindowAggState *winstate, int64 pos)
+{
+ Assert(winstate->reduced_frame_map != NULL);
+
+ if (pos < 0 || pos >= winstate->alloc_sz)
+ elog(ERROR, "wrong pos: " INT64_FORMAT, pos);
+
+ return winstate->reduced_frame_map[pos];
+}
+
+/*
+ * register_reduced_frame_map
+ * Add/replace reduced frame map member at pos.
+ * If there's no enough space, expand the map.
+ */
+static
+void
+register_reduced_frame_map(WindowAggState *winstate, int64 pos, int val)
+{
+ int64 realloc_sz;
+
+ Assert(winstate->reduced_frame_map != NULL);
+
+ if (pos < 0)
+ elog(ERROR, "wrong pos: " INT64_FORMAT, pos);
+
+ if (pos > winstate->alloc_sz - 1)
+ {
+ realloc_sz = winstate->alloc_sz * 2;
+
+ winstate->reduced_frame_map =
+ repalloc(winstate->reduced_frame_map, realloc_sz);
+
+ MemSet(winstate->reduced_frame_map + winstate->alloc_sz,
+ RF_NOT_DETERMINED, realloc_sz - winstate->alloc_sz);
+
+ winstate->alloc_sz = realloc_sz;
+ }
+
+ winstate->reduced_frame_map[pos] = val;
+}
+
+/*
+ * update_reduced_frame
+ * Update reduced frame info.
+ */
+static
+void
+update_reduced_frame(WindowObject winobj, int64 pos)
+{
+ WindowAggState *winstate = winobj->winstate;
+ ListCell *lc1,
+ *lc2;
+ bool expression_result;
+ int num_matched_rows;
+ int64 original_pos;
+ bool anymatch;
+ StringInfo encoded_str;
+ StringInfo pattern_str = makeStringInfo();
+ StringSet *str_set;
+ int initial_index;
+ VariablePos *variable_pos;
+ bool greedy = false;
+ int64 result_pos,
+ i;
+
+ /*
+ * Set of pattern variables evaluated to true. Each character corresponds
+ * to pattern variable. Example: str_set[0] = "AB"; str_set[1] = "AC"; In
+ * this case at row 0 A and B are true, and A and C are true in row 1.
+ */
+
+ /* initialize pattern variables set */
+ str_set = string_set_init();
+
+ /* save original pos */
+ original_pos = pos;
+
+ /*
+ * Check if the pattern does not include any greedy quantifier. If it does
+ * not, we can just apply the pattern to each row. If it succeeds, we are
+ * done.
+ */
+ foreach(lc1, winstate->patternRegexpList)
+ {
+ char *quantifier = strVal(lfirst(lc1));
+
+ if (*quantifier == '+' || *quantifier == '*')
+ {
+ greedy = true;
+ break;
+ }
+ }
+
+ /*
+ * Non greedy case
+ */
+ if (!greedy)
+ {
+ num_matched_rows = 0;
+
+ foreach(lc1, winstate->patternVariableList)
+ {
+ char *vname = strVal(lfirst(lc1));
+
+ encoded_str = makeStringInfo();
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s",
+ pos, vname);
+#endif
+ expression_result = false;
+
+ /* evaluate row pattern against current row */
+ result_pos = evaluate_pattern(winobj, pos, vname,
+ encoded_str, &expression_result);
+ if (!expression_result || result_pos < 0)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "expression result is false or out of frame");
+#endif
+ register_reduced_frame_map(winstate, original_pos,
+ RF_UNMATCHED);
+ return;
+ }
+ /* move to next row */
+ pos++;
+ num_matched_rows++;
+ }
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "pattern matched");
+#endif
+ register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD);
+
+ for (i = original_pos + 1; i < original_pos + num_matched_rows; i++)
+ {
+ register_reduced_frame_map(winstate, i, RF_SKIPPED);
+ }
+ return;
+ }
+
+ /*
+ * Greedy quantifiers included. Loop over until none of pattern matches or
+ * encounters end of frame.
+ */
+ for (;;)
+ {
+ result_pos = -1;
+
+ /*
+ * Loop over each PATTERN variable.
+ */
+ anymatch = false;
+ encoded_str = makeStringInfo();
+
+ forboth(lc1, winstate->patternVariableList, lc2,
+ winstate->patternRegexpList)
+ {
+ char *vname = strVal(lfirst(lc1));
+#ifdef RPR_DEBUG
+ char *quantifier = strVal(lfirst(lc2));
+
+ elog(DEBUG1, "pos: " INT64_FORMAT " pattern vname: %s quantifier: %s",
+ pos, vname, quantifier);
+#endif
+ expression_result = false;
+
+ /* evaluate row pattern against current row */
+ result_pos = evaluate_pattern(winobj, pos, vname,
+ encoded_str, &expression_result);
+ if (expression_result)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "expression result is true");
+#endif
+ anymatch = true;
+ }
+
+ /*
+ * If out of frame, we are done.
+ */
+ if (result_pos < 0)
+ break;
+ }
+
+ if (!anymatch)
+ {
+ /* none of patterns matched. */
+ break;
+ }
+
+ string_set_add(str_set, encoded_str);
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "pos: " INT64_FORMAT " encoded_str: %s",
+ encoded_str->data);
+#endif
+
+ /* move to next row */
+ pos++;
+
+ if (result_pos < 0)
+ {
+ /* out of frame */
+ break;
+ }
+ }
+
+ if (string_set_get_size(str_set) == 0)
+ {
+ /* no match found in the first row */
+ register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED);
+ return;
+ }
+
+#ifdef RPR_DEBUG
+ elog(DEBUG2, "pos: " INT64_FORMAT " encoded_str: %s",
+ pos, encoded_str->data);
+#endif
+
+ /* build regular expression */
+ pattern_str = makeStringInfo();
+ appendStringInfoChar(pattern_str, '^');
+ initial_index = 0;
+
+ variable_pos = variable_pos_init();
+
+ forboth(lc1, winstate->patternVariableList,
+ lc2, winstate->patternRegexpList)
+ {
+ char *vname = strVal(lfirst(lc1));
+ char *quantifier = strVal(lfirst(lc2));
+ char initial;
+
+ initial = pattern_initial(winstate, vname);
+ Assert(initial != 0);
+ appendStringInfoChar(pattern_str, initial);
+ if (quantifier[0])
+ appendStringInfoChar(pattern_str, quantifier[0]);
+
+ /*
+ * Register the initial at initial_index. If the initial appears more
+ * than once, all of it's initial_index will be recorded. This could
+ * happen if a pattern variable appears in the PATTERN clause more
+ * than once like "UP DOWN UP" "UP UP UP".
+ */
+ variable_pos_register(variable_pos, initial, initial_index);
+
+ initial_index++;
+ }
+
+#ifdef RPR_DEBUG
+ elog(DEBUG2, "pos: " INT64_FORMAT " pattern: %s",
+ pos, pattern_str->data);
+#endif
+
+ /* look for matching pattern variable sequence */
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "search_str_set started");
+#endif
+ num_matched_rows = search_str_set(pattern_str->data,
+ str_set, variable_pos);
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "search_str_set returns: %d", num_matched_rows);
+#endif
+ variable_pos_discard(variable_pos);
+ string_set_discard(str_set);
+
+ /*
+ * We are at the first row in the reduced frame. Save the number of
+ * matched rows as the number of rows in the reduced frame.
+ */
+ if (num_matched_rows <= 0)
+ {
+ /* no match */
+ register_reduced_frame_map(winstate, original_pos, RF_UNMATCHED);
+ }
+ else
+ {
+ register_reduced_frame_map(winstate, original_pos, RF_FRAME_HEAD);
+
+ for (i = original_pos + 1; i < original_pos + num_matched_rows; i++)
+ {
+ register_reduced_frame_map(winstate, i, RF_SKIPPED);
+ }
+ }
+
+ return;
+}
+
+/*
+ * search_str_set
+ * Perform pattern matching using "pattern" against str_set. pattern is a
+ * regular expression derived from PATTERN clause. Note that the regular
+ * expression string is prefixed by '^' and followed by initials represented
+ * in a same way as str_set. str_set is a set of StringInfo. Each StringInfo
+ * has a string comprising initials of pattern variable strings being true in
+ * a row. The initials are one of [a-y], parallel to the order of variable
+ * names in DEFINE clause. Suppose DEFINE has variables START, UP and DOWN. If
+ * PATTERN has START, UP+ and DOWN, then the initials in PATTERN will be 'a',
+ * 'b' and 'c'. The "pattern" will be "^ab+c".
+ *
+ * variable_pos is an array representing the order of pattern variable string
+ * initials in PATTERN clause. For example initial 'a' potion is in
+ * variable_pos[0].pos[0] = 0. Note that if the pattern is "START UP DOWN UP"
+ * (UP appears twice), then "UP" (initial is 'b') has two position 1 and
+ * 3. Thus variable_pos for b is variable_pos[1].pos[0] = 1 and
+ * variable_pos[1].pos[1] = 3.
+ *
+ * Returns the longest number of the matching rows (greedy matching) if
+ * quatifier '+' or '*' is included in "pattern".
+ */
+static
+int
+search_str_set(char *pattern, StringSet * str_set, VariablePos * variable_pos)
+{
+#define MAX_CANDIDATE_NUM 10000 /* max pattern match candidate size */
+#define FREEZED_CHAR 'Z' /* a pattern is freezed if it ends with the
+ * char */
+#define DISCARD_CHAR 'z' /* a pattern is not need to keep */
+
+ int set_size; /* number of rows in the set */
+ int resultlen;
+ int index;
+ StringSet *old_str_set,
+ *new_str_set;
+ int new_str_size;
+ int len;
+
+ set_size = string_set_get_size(str_set);
+ new_str_set = string_set_init();
+ len = 0;
+ resultlen = 0;
+
+ /*
+ * Generate all possible pattern variable name initials as a set of
+ * StringInfo named "new_str_set". For example, if we have two rows
+ * having "ab" (row 0) and "ac" (row 1) in the input str_set, new_str_set
+ * will have set of StringInfo "aa", "ac", "ba" and "bc" in the end.
+ */
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "pattern: %s set_size: %d", pattern, set_size);
+#endif
+ for (index = 0; index < set_size; index++)
+ {
+ StringInfo str; /* search target row */
+ char *p;
+ int old_set_size;
+ int i;
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "index: %d", index);
+#endif
+ if (index == 0)
+ {
+ /* copy variables in row 0 */
+ str = string_set_get(str_set, index);
+ p = str->data;
+
+ /*
+ * Loop over each new pattern variable char.
+ */
+ while (*p)
+ {
+ StringInfo new = makeStringInfo();
+
+ /* add pattern variable char */
+ appendStringInfoChar(new, *p);
+ /* add new one to string set */
+ string_set_add(new_str_set, new);
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "old_str: NULL new_str: %s", new->data);
+#endif
+ p++; /* next pattern variable */
+ }
+ }
+ else /* index != 0 */
+ {
+ old_str_set = new_str_set;
+ new_str_set = string_set_init();
+ str = string_set_get(str_set, index);
+ old_set_size = string_set_get_size(old_str_set);
+
+ /*
+ * Loop over each rows in the previous result set.
+ */
+ for (i = 0; i < old_set_size; i++)
+ {
+ StringInfo new;
+ char last_old_char;
+ int old_str_len;
+ StringInfo old = string_set_get(old_str_set, i);
+
+ p = old->data;
+ old_str_len = strlen(p);
+ if (old_str_len > 0)
+ last_old_char = p[old_str_len - 1];
+ else
+ last_old_char = '\0';
+
+ /* Is this old set freezed? */
+ if (last_old_char == FREEZED_CHAR)
+ {
+ /* if shorter match. we can discard it */
+ if ((old_str_len - 1) < resultlen)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "discard this old set because shorter match: %s",
+ old->data);
+#endif
+ continue;
+ }
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "keep this old set: %s", old->data);
+#endif
+
+ /* move the old set to new_str_set */
+ string_set_add(new_str_set, old);
+ old_str_set->str_set[i] = NULL;
+ continue;
+ }
+ /* Can this old set be discarded? */
+ else if (last_old_char == DISCARD_CHAR)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "discard this old set: %s", old->data);
+#endif
+ continue;
+ }
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "str->data: %s", str->data);
+#endif
+
+ /*
+ * loop over each pattern variable initial char in the input
+ * set.
+ */
+ for (p = str->data; *p; p++)
+ {
+ /*
+ * Optimization. Check if the row's pattern variable
+ * initial character position is greater than or equal to
+ * the old set's last pattern variable initial character
+ * position. For example, if the old set's last pattern
+ * variable initials are "ab", then the new pattern
+ * variable initial can be "b" or "c" but can not be "a",
+ * if the initials in PATTERN is something like "a b c" or
+ * "a b+ c+" etc. This optimization is possible when we
+ * only allow "+" quantifier.
+ */
+ if (variable_pos_compare(variable_pos, last_old_char, *p))
+ {
+ /* copy source string */
+ new = makeStringInfo();
+ enlargeStringInfo(new, old->len + 1);
+ appendStringInfoString(new, old->data);
+ /* add pattern variable char */
+ appendStringInfoChar(new, *p);
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "old_str: %s new_str: %s",
+ old->data, new->data);
+#endif
+
+ /*
+ * Adhoc optimization. If the first letter in the
+ * input string is the first and second position one
+ * and there's no associated quatifier '+', then we
+ * can dicard the input because there's no chace to
+ * expand the string further.
+ *
+ * For example, pattern "abc" cannot match "aa".
+ */
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "pattern[1]:%c pattern[2]:%c new[0]:%c new[1]:%c",
+ pattern[1], pattern[2], new->data[0], new->data[1]);
+#endif
+ if (pattern[1] == new->data[0] &&
+ pattern[1] == new->data[1] &&
+ pattern[2] != '+' &&
+ pattern[1] != pattern[2])
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "discard this new data: %s",
+ new->data);
+#endif
+ pfree(new->data);
+ pfree(new);
+ continue;
+ }
+
+ /* add new one to string set */
+ string_set_add(new_str_set, new);
+ }
+ else
+ {
+ /*
+ * We are freezing this pattern string. Since there's
+ * no chance to expand the string further, we perform
+ * pattern matching against the string. If it does not
+ * match, we can discard it.
+ */
+ len = do_pattern_match(pattern, old->data);
+
+ if (len <= 0)
+ {
+ /* no match. we can discard it */
+ continue;
+ }
+
+ else if (len <= resultlen)
+ {
+ /* shorter match. we can discard it */
+ continue;
+ }
+ else
+ {
+ /* match length is the longest so far */
+
+ int new_index;
+
+ /* remember the longest match */
+ resultlen = len;
+
+ /* freeze the pattern string */
+ new = makeStringInfo();
+ enlargeStringInfo(new, old->len + 1);
+ appendStringInfoString(new, old->data);
+ /* add freezed mark */
+ appendStringInfoChar(new, FREEZED_CHAR);
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "old_str: %s new_str: %s", old->data, new->data);
+#endif
+ string_set_add(new_str_set, new);
+
+ /*
+ * Search new_str_set to find out freezed entries
+ * that have shorter match length. Mark them as
+ * "discard" so that they are discarded in the
+ * next round.
+ */
+
+ /* new_index_size should be the one before */
+ new_str_size =
+ string_set_get_size(new_str_set) - 1;
+
+ /* loop over new_str_set */
+ for (new_index = 0; new_index < new_str_size;
+ new_index++)
+ {
+ char new_last_char;
+ int new_str_len;
+
+ new = string_set_get(new_str_set, new_index);
+ new_str_len = strlen(new->data);
+ if (new_str_len > 0)
+ {
+ new_last_char =
+ new->data[new_str_len - 1];
+ if (new_last_char == FREEZED_CHAR &&
+ (new_str_len - 1) <= len)
+ {
+ /*
+ * mark this set to discard in the
+ * next round
+ */
+ appendStringInfoChar(new, DISCARD_CHAR);
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "add discard char: %s", new->data);
+#endif
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+ /* we no longer need old string set */
+ string_set_discard(old_str_set);
+ }
+ }
+
+ /*
+ * Perform pattern matching to find out the longest match.
+ */
+ new_str_size = string_set_get_size(new_str_set);
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "new_str_size: %d", new_str_size);
+#endif
+ len = 0;
+ resultlen = 0;
+
+ for (index = 0; index < new_str_size; index++)
+ {
+ StringInfo s;
+
+ s = string_set_get(new_str_set, index);
+ if (s == NULL)
+ continue; /* no data */
+
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "target string: %s", s->data);
+#endif
+ len = do_pattern_match(pattern, s->data);
+ if (len > resultlen)
+ {
+ /* remember the longest match */
+ resultlen = len;
+
+ /*
+ * If the size of result set is equal to the number of rows in the
+ * set, we are done because it's not possible that the number of
+ * matching rows exceeds the number of rows in the set.
+ */
+ if (resultlen >= set_size)
+ break;
+ }
+ }
+
+ /* we no longer need new string set */
+ string_set_discard(new_str_set);
+
+ return resultlen;
+}
+
+/*
+ * do_pattern_match
+ * perform pattern match using pattern against encoded_str.
+ * returns matching number of rows if matching is succeeded.
+ * Otherwise returns 0.
+ */
+static
+int
+do_pattern_match(char *pattern, char *encoded_str)
+{
+ Datum d;
+ text *res;
+ char *substr;
+ int len = 0;
+ text *pattern_text,
+ *encoded_str_text;
+
+ pattern_text = cstring_to_text(pattern);
+ encoded_str_text = cstring_to_text(encoded_str);
+
+ /*
+ * We first perform pattern matching using regexp_instr, then call
+ * textregexsubstr to get matched substring to know how long the matched
+ * string is. That is the number of rows in the reduced window frame. The
+ * reason why we can't call textregexsubstr in the first place is, it
+ * errors out if pattern does not match.
+ */
+ if (DatumGetInt32(DirectFunctionCall2Coll(
+ regexp_instr, DEFAULT_COLLATION_OID,
+ PointerGetDatum(encoded_str_text),
+ PointerGetDatum(pattern_text))))
+ {
+ d = DirectFunctionCall2Coll(textregexsubstr,
+ DEFAULT_COLLATION_OID,
+ PointerGetDatum(encoded_str_text),
+ PointerGetDatum(pattern_text));
+ if (d != 0)
+ {
+ res = DatumGetTextPP(d);
+ substr = text_to_cstring(res);
+ len = strlen(substr);
+ pfree(substr);
+ }
+ }
+ pfree(encoded_str_text);
+ pfree(pattern_text);
+
+ return len;
+}
+
+/*
+ * evaluate_pattern
+ * Evaluate expression associated with PATTERN variable vname. current_pos is
+ * relative row position in a frame (starting from 0). If vname is evaluated
+ * to true, initial letters associated with vname is appended to
+ * encode_str. result is out paramater representing the expression evaluation
+ * result is true of false.
+ *---------
+ * Return values are:
+ * >=0: the last match absolute row position
+ * otherwise out of frame.
+ *---------
+ */
+static
+int64
+evaluate_pattern(WindowObject winobj, int64 current_pos,
+ char *vname, StringInfo encoded_str, bool *result)
+{
+ WindowAggState *winstate = winobj->winstate;
+ ExprContext *econtext = winstate->ss.ps.ps_ExprContext;
+ ListCell *lc1,
+ *lc2,
+ *lc3;
+ ExprState *pat;
+ Datum eval_result;
+ bool out_of_frame = false;
+ bool isnull;
+ TupleTableSlot *slot;
+
+ forthree(lc1, winstate->defineVariableList,
+ lc2, winstate->defineClauseList,
+ lc3, winstate->defineInitial)
+ {
+ char initial; /* initial letter associated with vname */
+ char *name = strVal(lfirst(lc1));
+
+ if (strcmp(vname, name))
+ continue;
+
+ initial = *(strVal(lfirst(lc3)));
+
+ /* set expression to evaluate */
+ pat = lfirst(lc2);
+
+ /* get current, previous and next tuples */
+ if (!get_slots(winobj, current_pos))
+ {
+ out_of_frame = true;
+ }
+ else
+ {
+ /* evaluate the expression */
+ eval_result = ExecEvalExpr(pat, econtext, &isnull);
+ if (isnull)
+ {
+ /* expression is NULL */
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "expression for %s is NULL at row: " INT64_FORMAT,
+ vname, current_pos);
+#endif
+ *result = false;
+ }
+ else
+ {
+ if (!DatumGetBool(eval_result))
+ {
+ /* expression is false */
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "expression for %s is false at row: " INT64_FORMAT,
+ vname, current_pos);
+#endif
+ *result = false;
+ }
+ else
+ {
+ /* expression is true */
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "expression for %s is true at row: " INT64_FORMAT,
+ vname, current_pos);
+#endif
+ appendStringInfoChar(encoded_str, initial);
+ *result = true;
+ }
+ }
+
+ slot = winstate->temp_slot_1;
+ if (slot != winstate->null_slot)
+ ExecClearTuple(slot);
+ slot = winstate->prev_slot;
+ if (slot != winstate->null_slot)
+ ExecClearTuple(slot);
+ slot = winstate->next_slot;
+ if (slot != winstate->null_slot)
+ ExecClearTuple(slot);
+
+ break;
+ }
+
+ if (out_of_frame)
+ {
+ *result = false;
+ return -1;
+ }
+ }
+ return current_pos;
+}
+
+/*
+ * get_slots
+ * Get current, previous and next tuples.
+ * Returns false if current row is out of partition/full frame.
+ */
+static
+bool
+get_slots(WindowObject winobj, int64 current_pos)
+{
+ WindowAggState *winstate = winobj->winstate;
+ TupleTableSlot *slot;
+ int ret;
+ ExprContext *econtext;
+
+ econtext = winstate->ss.ps.ps_ExprContext;
+
+ /* set up current row tuple slot */
+ slot = winstate->temp_slot_1;
+ if (!window_gettupleslot(winobj, current_pos, slot))
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "current row is out of partition at:" INT64_FORMAT,
+ current_pos);
+#endif
+ return false;
+ }
+ ret = row_is_in_frame(winstate, current_pos, slot);
+ if (ret <= 0)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "current row is out of frame at: " INT64_FORMAT,
+ current_pos);
+#endif
+ ExecClearTuple(slot);
+ return false;
+ }
+ econtext->ecxt_outertuple = slot;
+
+ /* for PREV */
+ if (current_pos > 0)
+ {
+ slot = winstate->prev_slot;
+ if (!window_gettupleslot(winobj, current_pos - 1, slot))
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "previous row is out of partition at: " INT64_FORMAT,
+ current_pos - 1);
+#endif
+ econtext->ecxt_scantuple = winstate->null_slot;
+ }
+ else
+ {
+ ret = row_is_in_frame(winstate, current_pos - 1, slot);
+ if (ret <= 0)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "previous row is out of frame at: " INT64_FORMAT,
+ current_pos - 1);
+#endif
+ ExecClearTuple(slot);
+ econtext->ecxt_scantuple = winstate->null_slot;
+ }
+ else
+ {
+ econtext->ecxt_scantuple = slot;
+ }
+ }
+ }
+ else
+ econtext->ecxt_scantuple = winstate->null_slot;
+
+ /* for NEXT */
+ slot = winstate->next_slot;
+ if (!window_gettupleslot(winobj, current_pos + 1, slot))
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "next row is out of partiton at: " INT64_FORMAT,
+ current_pos + 1);
+#endif
+ econtext->ecxt_innertuple = winstate->null_slot;
+ }
+ else
+ {
+ ret = row_is_in_frame(winstate, current_pos + 1, slot);
+ if (ret <= 0)
+ {
+#ifdef RPR_DEBUG
+ elog(DEBUG1, "next row is out of frame at: " INT64_FORMAT,
+ current_pos + 1);
+#endif
+ ExecClearTuple(slot);
+ econtext->ecxt_innertuple = winstate->null_slot;
+ }
+ else
+ econtext->ecxt_innertuple = slot;
+ }
+ return true;
+}
+
+/*
+ * pattern_initial
+ * Return pattern variable initial character
+ * matching with pattern variable name vname.
+ * If not found, return 0.
+ */
+static
+char
+pattern_initial(WindowAggState *winstate, char *vname)
+{
+ char initial;
+ char *name;
+ ListCell *lc1,
+ *lc2;
+
+ forboth(lc1, winstate->defineVariableList,
+ lc2, winstate->defineInitial)
+ {
+ name = strVal(lfirst(lc1)); /* DEFINE variable name */
+ initial = *(strVal(lfirst(lc2))); /* DEFINE variable initial */
+
+
+ if (!strcmp(name, vname))
+ return initial; /* found */
+ }
+ return 0;
+}
+
+/*
+ * string_set_init
+ * Create dynamic set of StringInfo.
+ */
+static
+StringSet * string_set_init(void)
+{
+/* Initial allocation size of str_set */
+#define STRING_SET_ALLOC_SIZE 1024
+
+ StringSet *string_set;
+ Size set_size;
+
+ string_set = palloc0(sizeof(StringSet));
+ string_set->set_index = 0;
+ set_size = STRING_SET_ALLOC_SIZE;
+ string_set->str_set = palloc(set_size * sizeof(StringInfo));
+ string_set->set_size = set_size;
+
+ return string_set;
+}
+
+/*
+ * string_set_add
+ * Add StringInfo str to StringSet string_set.
+ */
+static
+void
+string_set_add(StringSet * string_set, StringInfo str)
+{
+ Size set_size;
+
+ set_size = string_set->set_size;
+ if (string_set->set_index >= set_size)
+ {
+ set_size *= 2;
+ string_set->str_set = repalloc(string_set->str_set,
+ set_size * sizeof(StringInfo));
+ string_set->set_size = set_size;
+ }
+
+ string_set->str_set[string_set->set_index++] = str;
+
+ return;
+}
+
+/*
+ * string_set_get
+ * Returns StringInfo specified by index.
+ * If there's no data yet, returns NULL.
+ */
+static
+StringInfo
+string_set_get(StringSet * string_set, int index)
+{
+ /* no data? */
+ if (index == 0 && string_set->set_index == 0)
+ return NULL;
+
+ if (index < 0 || index >= string_set->set_index)
+ elog(ERROR, "invalid index: %d", index);
+
+ return string_set->str_set[index];
+}
+
+/*
+ * string_set_get_size
+ * Returns the size of StringSet.
+ */
+static
+int
+string_set_get_size(StringSet * string_set)
+{
+ return string_set->set_index;
+}
+
+/*
+ * string_set_discard
+ * Discard StringSet.
+ * All memory including StringSet itself is freed.
+ */
+static
+void
+string_set_discard(StringSet * string_set)
+{
+ int i;
+
+ for (i = 0; i < string_set->set_index; i++)
+ {
+ StringInfo str = string_set->str_set[i];
+
+ if (str)
+ {
+ pfree(str->data);
+ pfree(str);
+ }
+ }
+ pfree(string_set->str_set);
+ pfree(string_set);
+}
+
+/*
+ * variable_pos_init
+ * Create and initialize variable postion structure
+ */
+static
+VariablePos * variable_pos_init(void)
+{
+ VariablePos *variable_pos;
+
+ variable_pos = palloc(sizeof(VariablePos) * NUM_ALPHABETS);
+ MemSet(variable_pos, -1, sizeof(VariablePos) * NUM_ALPHABETS);
+ return variable_pos;
+}
+
+/*
+ * variable_pos_register
+ * Register pattern variable whose initial is initial into postion index.
+ * pos is position of initial.
+ * If pos is already registered, register it at next empty slot.
+ */
+static
+void
+variable_pos_register(VariablePos * variable_pos, char initial, int pos)
+{
+ int index = initial - 'a';
+ int slot;
+ int i;
+
+ if (pos < 0 || pos > NUM_ALPHABETS)
+ elog(ERROR, "initial is not valid char: %c", initial);
+
+ for (i = 0; i < NUM_ALPHABETS; i++)
+ {
+ slot = variable_pos[index].pos[i];
+ if (slot < 0)
+ {
+ /* empty slot found */
+ variable_pos[index].pos[i] = pos;
+ return;
+ }
+ }
+ elog(ERROR, "no empty slot for initial: %c", initial);
+}
+
+/*
+ * variable_pos_compare
+ * Returns true if initial1 can be followed by initial2
+ */
+static
+bool
+variable_pos_compare(VariablePos * variable_pos, char initial1, char initial2)
+{
+ int index1,
+ index2;
+ int pos1,
+ pos2;
+
+ for (index1 = 0;; index1++)
+ {
+ pos1 = variable_pos_fetch(variable_pos, initial1, index1);
+ if (pos1 < 0)
+ break;
+
+ for (index2 = 0;; index2++)
+ {
+ pos2 = variable_pos_fetch(variable_pos, initial2, index2);
+ if (pos2 < 0)
+ break;
+ if (pos1 <= pos2)
+ return true;
+ }
+ }
+ return false;
+}
+
+/*
+ * variable_pos_fetch
+ * Fetch position of pattern variable whose initial is initial, and whose index
+ * is index. If no postion was registered by initial, index, returns -1.
+ */
+static
+int
+variable_pos_fetch(VariablePos * variable_pos, char initial, int index)
+{
+ int pos = initial - 'a';
+
+ if (pos < 0 || pos > NUM_ALPHABETS)
+ elog(ERROR, "initial is not valid char: %c", initial);
+
+ if (index < 0 || index > NUM_ALPHABETS)
+ elog(ERROR, "index is not valid: %d", index);
+
+ return variable_pos[pos].pos[index];
+}
+
+/*
+ * variable_pos_discard
+ * Discard VariablePos
+ */
+static
+void
+variable_pos_discard(VariablePos * variable_pos)
+{
+ pfree(variable_pos);
+}
diff --git a/src/backend/utils/adt/windowfuncs.c b/src/backend/utils/adt/windowfuncs.c
index 473c61569f..92c528d38c 100644
--- a/src/backend/utils/adt/windowfuncs.c
+++ b/src/backend/utils/adt/windowfuncs.c
@@ -13,6 +13,9 @@
*/
#include "postgres.h"
+#include "catalog/pg_collation_d.h"
+#include "executor/executor.h"
+#include "nodes/execnodes.h"
#include "nodes/parsenodes.h"
#include "nodes/supportnodes.h"
#include "utils/fmgrprotos.h"
@@ -37,11 +40,19 @@ typedef struct
int64 remainder; /* (total rows) % (bucket num) */
} ntile_context;
+/*
+ * rpr process information.
+ * Used for AFTER MATCH SKIP PAST LAST ROW
+ */
+typedef struct SkipContext
+{
+ int64 pos; /* last row absolute position */
+} SkipContext;
+
static bool rank_up(WindowObject winobj);
static Datum leadlag_common(FunctionCallInfo fcinfo,
bool forward, bool withoffset, bool withdefault);
-
/*
* utility routine for *_rank functions.
*/
@@ -674,7 +685,7 @@ window_last_value(PG_FUNCTION_ARGS)
bool isnull;
result = WinGetFuncArgInFrame(winobj, 0,
- 0, WINDOW_SEEK_TAIL, true,
+ 0, WINDOW_SEEK_TAIL, false,
&isnull, NULL);
if (isnull)
PG_RETURN_NULL();
@@ -714,3 +725,25 @@ window_nth_value(PG_FUNCTION_ARGS)
PG_RETURN_DATUM(result);
}
+
+/*
+ * prev
+ * Dummy function to invoke RPR's navigation operator "PREV".
+ * This is *not* a window function.
+ */
+Datum
+window_prev(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_DATUM(PG_GETARG_DATUM(0));
+}
+
+/*
+ * next
+ * Dummy function to invoke RPR's navigation operation "NEXT".
+ * This is *not* a window function.
+ */
+Datum
+window_next(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_DATUM(PG_GETARG_DATUM(0));
+}
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 43f608d7a0..6a301920f9 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -10604,6 +10604,12 @@
{ oid => '3114', descr => 'fetch the Nth row value',
proname => 'nth_value', prokind => 'w', prorettype => 'anyelement',
proargtypes => 'anyelement int4', prosrc => 'window_nth_value' },
+{ oid => '6122', descr => 'previous value',
+ proname => 'prev', provolatile => 's', prorettype => 'anyelement',
+ proargtypes => 'anyelement', prosrc => 'window_prev' },
+{ oid => '6123', descr => 'next value',
+ proname => 'next', provolatile => 's', prorettype => 'anyelement',
+ proargtypes => 'anyelement', prosrc => 'window_next' },
# functions for range types
{ oid => '3832', descr => 'I/O',
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 88467977f8..058cef2121 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -2581,6 +2581,11 @@ typedef enum WindowAggStatus
* tuples during spool */
} WindowAggStatus;
+#define RF_NOT_DETERMINED 0
+#define RF_FRAME_HEAD 1
+#define RF_SKIPPED 2
+#define RF_UNMATCHED 3
+
typedef struct WindowAggState
{
ScanState ss; /* its first field is NodeTag */
@@ -2640,6 +2645,19 @@ typedef struct WindowAggState
int64 groupheadpos; /* current row's peer group head position */
int64 grouptailpos; /* " " " " tail position (group end+1) */
+ /* these fields are used in Row pattern recognition: */
+ RPSkipTo rpSkipTo; /* Row Pattern Skip To type */
+ List *patternVariableList; /* list of row pattern variables names
+ * (list of String) */
+ List *patternRegexpList; /* list of row pattern regular expressions
+ * ('+' or ''. list of String) */
+ List *defineVariableList; /* list of row pattern definition
+ * variables (list of String) */
+ List *defineClauseList; /* expression for row pattern definition
+ * search conditions ExprState list */
+ List *defineInitial; /* list of row pattern definition variable
+ * initials (list of String) */
+
MemoryContext partcontext; /* context for partition-lifespan data */
MemoryContext aggcontext; /* shared context for aggregate working data */
MemoryContext curaggcontext; /* current aggregate's working data */
@@ -2667,6 +2685,18 @@ typedef struct WindowAggState
TupleTableSlot *agg_row_slot;
TupleTableSlot *temp_slot_1;
TupleTableSlot *temp_slot_2;
+
+ /* temporary slots for RPR */
+ TupleTableSlot *prev_slot; /* PREV row navigation operator */
+ TupleTableSlot *next_slot; /* NEXT row navigation operator */
+ TupleTableSlot *null_slot; /* all NULL slot */
+
+ /*
+ * Each byte corresponds to a row positioned at absolute its pos in
+ * partition. See above definition for RF_*
+ */
+ char *reduced_frame_map;
+ int64 alloc_sz; /* size of the map */
} WindowAggState;
/* ----------------
--
2.25.1
----Next_Part(Thu_Sep_19_13_59_47_2024_608)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="v22-0006-Row-pattern-recognition-patch-docs.patch"
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2023-08-29 16:46 Re: pg_stat_get_backend_subxact() and backend IDs? Nathan Bossart <[email protected]>
2023-08-29 23:22 ` Michael Paquier <[email protected]>
2023-08-30 02:01 ` Nathan Bossart <[email protected]>
2023-08-30 04:13 ` Michael Paquier <[email protected]>
2023-08-30 13:50 ` Robert Haas <[email protected]>
2023-08-30 14:27 ` Nathan Bossart <[email protected]>
2023-08-30 14:56 ` Robert Haas <[email protected]>
2023-08-30 21:56 ` Nathan Bossart <[email protected]>
2023-08-31 04:22 ` Michael Paquier <[email protected]>
2023-08-31 11:17 ` Dilip Kumar <[email protected]>
2023-09-18 06:52 ` Ian Lawrence Barwick <[email protected]>
2024-09-19 04:48 [PATCH v22 5/8] Row pattern recognition patch (executor). Tatsuo Ishii <[email protected]>
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