postgres.git / summary / log / commit / refs
commit c7cdcbd3e6a72f858690ed7e69046cf2cd41fb19
Author: Michael Paquier <michael@paquier.xyz>
Date: Sat Apr 11 08:03:08 2026 +0000
First released in: 15.18, 16.14, 17.10, 18.4
Honor passed-in database OIDs in pgstat_database.c
Three routines in pgstat_database.c incorrectly ignore the database OID
provided by their caller, using MyDatabaseId instead:
- pgstat_report_connect()
- pgstat_report_disconnect()
- pgstat_reset_database_timestamp()
The first two functions, for connection and disconnection, each have a
single caller that already passes MyDatabaseId. This was harmless,
still incorrect.
The timestamp reset function also has a single caller, but in this case
the issue has a real impact: it fails to reset the timestamp for the
shared-database entry (datid=0) when operating on shared objects. This
situation can occur, for example, when resetting counters for shared
relations via pg_stat_reset_single_table_counters().
There is currently one test in the tree that checks the reset of a
shared relation, for pg_shdescription, we rely on it to check what is
stored in pg_stat_database. As stats_reset may be NULL, two resets are
done to provide a baseline for comparison.
Author: Chao Li <li.evan.chao@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Dapeng Wang <wangdp20191008@gmail.com>
Discussion: https://postgr.es/m/ABBD5026-506F-4006-A569-28F72C188693@gmail.com
Backpatch-through: 15
src/backend/utils/activity/pgstat_database.c | 6 +++---
src/test/regress/expected/stats.out | 18 ++++++++++++++++++
src/test/regress/sql/stats.sql | 8 ++++++++
3 files changed, 29 insertions(+), 3 deletions(-)
diff --git a/src/backend/utils/activity/pgstat_database.c b/src/backend/utils/activity/pgstat_database.c
index 813aa359fa0..91cf0fd346a 100644
--- a/src/backend/utils/activity/pgstat_database.c
+++ b/src/backend/utils/activity/pgstat_database.c
@@ -197,7 +197,7 @@ pgstat_report_connect(Oid dboid)
pgLastSessionReportTime = MyStartTimestamp;
- dbentry = pgstat_prep_database_pending(MyDatabaseId);
+ dbentry = pgstat_prep_database_pending(dboid);
dbentry->sessions++;
}
@@ -212,7 +212,7 @@ pgstat_report_disconnect(Oid dboid)
if (!pgstat_should_report_connstat())
return;
- dbentry = pgstat_prep_database_pending(MyDatabaseId);
+ dbentry = pgstat_prep_database_pending(dboid);
switch (pgStatSessionEndCause)
{
@@ -356,7 +356,7 @@ pgstat_reset_database_timestamp(Oid dboid, TimestampTz ts)
PgStat_EntryRef *dbref;
PgStatShared_Database *dbentry;
- dbref = pgstat_get_entry_ref_locked(PGSTAT_KIND_DATABASE, MyDatabaseId, InvalidOid,
+ dbref = pgstat_get_entry_ref_locked(PGSTAT_KIND_DATABASE, dboid, InvalidOid,
false);
dbentry = (PgStatShared_Database *) dbref->shared_stats;
diff --git a/src/test/regress/expected/stats.out b/src/test/regress/expected/stats.out
index 94187e59cfb..00efcedc99a 100644
--- a/src/test/regress/expected/stats.out
+++ b/src/test/regress/expected/stats.out
@@ -791,6 +791,8 @@ SELECT (n_tup_ins + n_tup_upd) > 0 AS has_data FROM pg_stat_all_tables
t
(1 row)
+-- stats_reset may not be set for datid=0 and shared objects in
+-- pg_stat_database, so reset once.
SELECT pg_stat_reset_single_table_counters('pg_shdescription'::regclass);
pg_stat_reset_single_table_counters
-------------------------------------
@@ -804,6 +806,22 @@ SELECT (n_tup_ins + n_tup_upd) > 0 AS has_data FROM pg_stat_all_tables
f
(1 row)
+SELECT stats_reset AS shared_db_reset_before
+ FROM pg_stat_database WHERE datid = 0 \gset
+-- Second reset for comparison.
+SELECT pg_stat_reset_single_table_counters('pg_shdescription'::regclass);
+ pg_stat_reset_single_table_counters
+-------------------------------------
+
+(1 row)
+
+SELECT stats_reset > :'shared_db_reset_before'::timestamptz AS has_updated
+ FROM pg_stat_database WHERE datid = 0;
+ has_updated
+-------------
+ t
+(1 row)
+
-- set back comment
\if :{?description_before}
COMMENT ON DATABASE :"datname" IS :'description_before';
diff --git a/src/test/regress/sql/stats.sql b/src/test/regress/sql/stats.sql
index 1e21e55c6d9..44952a7d64b 100644
--- a/src/test/regress/sql/stats.sql
+++ b/src/test/regress/sql/stats.sql
@@ -396,9 +396,17 @@ COMMIT;
-- check that the stats are reset.
SELECT (n_tup_ins + n_tup_upd) > 0 AS has_data FROM pg_stat_all_tables
WHERE relid = 'pg_shdescription'::regclass;
+-- stats_reset may not be set for datid=0 and shared objects in
+-- pg_stat_database, so reset once.
SELECT pg_stat_reset_single_table_counters('pg_shdescription'::regclass);
SELECT (n_tup_ins + n_tup_upd) > 0 AS has_data FROM pg_stat_all_tables
WHERE relid = 'pg_shdescription'::regclass;
+SELECT stats_reset AS shared_db_reset_before
+ FROM pg_stat_database WHERE datid = 0 \gset
+-- Second reset for comparison.
+SELECT pg_stat_reset_single_table_counters('pg_shdescription'::regclass);
+SELECT stats_reset > :'shared_db_reset_before'::timestamptz AS has_updated
+ FROM pg_stat_database WHERE datid = 0;
-- set back comment
\if :{?description_before}
[parent: e630f65d0304]