From 299c8bea787fb1637b58390d351a07aaa2521ac9 Mon Sep 17 00:00:00 2001 From: Nathan Bossart Date: Wed, 23 Apr 2025 10:37:42 -0500 Subject: [PATCH v2 2/2] vacuumdb: Don't skip empty relations in --missing-stats-only. Presently, --missing-stats-only skips relations with reltuples set to 0 because empty relations don't get optimizer statistics. However, before v14, a reltuples value of 0 was ambiguous: it could either mean the relation is empty, or it could mean that it hadn't yet been vacuumed or analyzed. (Commit 3d351d916b taught Postgres 14 and newer to use -1 for the latter case.) This ambiguity can cause --missing-stats-only to inadvertently skip relations that need optimizer statistics. To fix, simply remove the check for reltuples != 0. This will cause --missing-stats-only to analyze some empty tables, but that doesn't seem too terrible a trade-off. Reported-by: Christoph Berg Reviewed-by: Christoph Berg Discussion: https://postgr.es/m/aAjyvW5_fRGNr7yF%40msg.df7cb.de --- src/bin/scripts/vacuumdb.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/src/bin/scripts/vacuumdb.c b/src/bin/scripts/vacuumdb.c index 22067faaf7d..79b1096eb08 100644 --- a/src/bin/scripts/vacuumdb.c +++ b/src/bin/scripts/vacuumdb.c @@ -954,7 +954,6 @@ retrieve_objects(PGconn *conn, vacuumingOptions *vacopts, appendPQExpBufferStr(&catalog_query, " EXISTS (SELECT NULL FROM pg_catalog.pg_attribute a\n" " WHERE a.attrelid OPERATOR(pg_catalog.=) c.oid\n" - " AND c.reltuples OPERATOR(pg_catalog.!=) 0::pg_catalog.float4\n" " AND a.attnum OPERATOR(pg_catalog.>) 0::pg_catalog.int2\n" " AND NOT a.attisdropped\n" " AND a.attstattarget IS DISTINCT FROM 0::pg_catalog.int2\n" @@ -967,7 +966,6 @@ retrieve_objects(PGconn *conn, vacuumingOptions *vacopts, appendPQExpBufferStr(&catalog_query, " OR EXISTS (SELECT NULL FROM pg_catalog.pg_statistic_ext e\n" " WHERE e.stxrelid OPERATOR(pg_catalog.=) c.oid\n" - " AND c.reltuples OPERATOR(pg_catalog.!=) 0::pg_catalog.float4\n" " AND e.stxstattarget IS DISTINCT FROM 0::pg_catalog.int2\n" " AND NOT EXISTS (SELECT NULL FROM pg_catalog.pg_statistic_ext_data d\n" " WHERE d.stxoid OPERATOR(pg_catalog.=) e.oid\n" @@ -979,7 +977,6 @@ retrieve_objects(PGconn *conn, vacuumingOptions *vacopts, " JOIN pg_catalog.pg_index i" " ON i.indexrelid OPERATOR(pg_catalog.=) a.attrelid\n" " WHERE i.indrelid OPERATOR(pg_catalog.=) c.oid\n" - " AND c.reltuples OPERATOR(pg_catalog.!=) 0::pg_catalog.float4\n" " AND i.indkey[a.attnum OPERATOR(pg_catalog.-) 1::pg_catalog.int2]" " OPERATOR(pg_catalog.=) 0::pg_catalog.int2\n" " AND a.attnum OPERATOR(pg_catalog.>) 0::pg_catalog.int2\n" @@ -994,7 +991,6 @@ retrieve_objects(PGconn *conn, vacuumingOptions *vacopts, appendPQExpBufferStr(&catalog_query, " OR EXISTS (SELECT NULL FROM pg_catalog.pg_attribute a\n" " WHERE a.attrelid OPERATOR(pg_catalog.=) c.oid\n" - " AND c.reltuples OPERATOR(pg_catalog.!=) 0::pg_catalog.float4\n" " AND a.attnum OPERATOR(pg_catalog.>) 0::pg_catalog.int2\n" " AND NOT a.attisdropped\n" " AND a.attstattarget IS DISTINCT FROM 0::pg_catalog.int2\n" @@ -1011,7 +1007,6 @@ retrieve_objects(PGconn *conn, vacuumingOptions *vacopts, appendPQExpBufferStr(&catalog_query, " OR EXISTS (SELECT NULL FROM pg_catalog.pg_statistic_ext e\n" " WHERE e.stxrelid OPERATOR(pg_catalog.=) c.oid\n" - " AND c.reltuples OPERATOR(pg_catalog.!=) 0::pg_catalog.float4\n" " AND e.stxstattarget IS DISTINCT FROM 0::pg_catalog.int2\n" " AND c.relhassubclass\n" " AND NOT p.inherited\n" -- 2.39.5 (Apple Git-154)