From 07233335f92cf7eaffedfcc56d9849b962617ee2 Mon Sep 17 00:00:00 2001 From: xiaoyu liu Date: Thu, 3 Sep 2026 09:59:27 +0800 Subject: [PATCH v3 2/2] psql: filter system objects before visibility checks When describe commands hide system objects, filter pg_catalog and information_schema using namespace OIDs from the object catalogs. This lets the namespace restriction be applied during the catalog scan and avoids unnecessary visibility checks and cache population. Centralize construction of the filter in appendSystemSchemaFilter() and reuse it in the affected describe queries. --- src/bin/psql/describe.c | 88 +++++++++++++++++++++++------------------ 1 file changed, 50 insertions(+), 38 deletions(-) diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c index 0bc9f39a124..22509bc9f71 100644 --- a/src/bin/psql/describe.c +++ b/src/bin/psql/describe.c @@ -54,6 +54,9 @@ static bool describeOneTSConfig(const char *oid, const char *nspname, const char *pnspname, const char *prsname); static void printACLColumn(PQExpBuffer buf, const char *colname); static bool listOneExtensionContents(const char *extname, const char *oid); +static void appendSystemSchemaFilter(PQExpBuffer buf, + const char *namespacevar, + bool have_where); static bool validateSQLNamePattern(PQExpBuffer buf, const char *pattern, bool have_where, bool force_escape, const char *schemavar, const char *namevar, @@ -114,8 +117,7 @@ describeAggregates(const char *pattern, bool verbose, bool showSystem) gettext_noop("Description")); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "p.pronamespace", true); if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "p.proname", NULL, @@ -546,6 +548,12 @@ describeFunctions(const char *functypes, const char *func_pattern, appendPQExpBufferStr(&buf, " )\n"); } + if (!showSystem && !func_pattern) + { + appendSystemSchemaFilter(&buf, "p.pronamespace", have_where); + have_where = true; + } + if (!validateSQLNamePattern(&buf, func_pattern, have_where, false, "n.nspname", "p.proname", NULL, "pg_catalog.pg_function_is_visible(p.oid)", @@ -586,10 +594,6 @@ describeFunctions(const char *functypes, const char *func_pattern, } } - if (!showSystem && !func_pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); - appendPQExpBufferStr(&buf, "ORDER BY 1, 2, 4;"); res = PSQLexec(buf.data); @@ -684,8 +688,7 @@ describeTypes(const char *pattern, bool verbose, bool showSystem) appendPQExpBufferStr(&buf, " AND NOT EXISTS(SELECT 1 FROM pg_catalog.pg_type el WHERE el.oid = t.typelem AND el.typarray = t.oid)\n"); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "t.typnamespace", true); /* Match name pattern against either internal or external name */ if (!validateSQLNamePattern(&buf, map_typename_pattern(pattern), @@ -852,8 +855,7 @@ describeOperators(const char *oper_pattern, " LEFT JOIN pg_catalog.pg_proc p ON p.oid = o.oprcode\n"); if (!showSystem && !oper_pattern) - appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "o.oprnamespace", false); if (!validateSQLNamePattern(&buf, oper_pattern, !showSystem && !oper_pattern, true, @@ -1132,8 +1134,7 @@ permissionsList(const char *pattern, bool showSystem) CppAsString2(RELKIND_PARTITIONED_TABLE) ")\n"); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "c.relnamespace", true); if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "c.relname", NULL, @@ -1285,8 +1286,7 @@ objectDescription(const char *pattern, bool showSystem) gettext_noop("table constraint")); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "c.relnamespace", false); if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern, false, "n.nspname", "pgc.conname", NULL, @@ -1309,8 +1309,7 @@ objectDescription(const char *pattern, bool showSystem) gettext_noop("domain constraint")); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "t.typnamespace", false); if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern, false, "n.nspname", "pgc.conname", NULL, @@ -1333,8 +1332,7 @@ objectDescription(const char *pattern, bool showSystem) gettext_noop("operator class")); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "o.opcnamespace", true); if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "o.opcname", NULL, @@ -1357,8 +1355,7 @@ objectDescription(const char *pattern, bool showSystem) gettext_noop("operator family")); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "opf.opfnamespace", true); if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "opf.opfname", NULL, @@ -1380,8 +1377,7 @@ objectDescription(const char *pattern, bool showSystem) gettext_noop("rule")); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "c.relnamespace", true); if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "r.rulename", NULL, @@ -1402,8 +1398,7 @@ objectDescription(const char *pattern, bool showSystem) gettext_noop("trigger")); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "c.relnamespace", false); if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern, false, "n.nspname", "t.tgname", NULL, @@ -1465,8 +1460,7 @@ describeTableDetails(const char *pattern, bool verbose, bool showSystem) " JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n"); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "c.relnamespace", false); if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern, false, "n.nspname", "c.relname", NULL, @@ -4229,9 +4223,10 @@ listTables(const char *tabtypes, const char *pattern, bool verbose, bool showSys appendPQExpBufferStr(&buf, ")\n"); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname !~ '^pg_toast'\n" - " AND n.nspname <> 'information_schema'\n"); + { + appendSystemSchemaFilter(&buf, "c.relnamespace", true); + appendPQExpBufferStr(&buf, " AND n.nspname !~ '^pg_toast'\n"); + } if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "c.relname", NULL, @@ -4502,9 +4497,10 @@ listPartitionedTables(const char *reltypes, const char *pattern, bool verbose) " AND NOT c.relispartition\n" : ""); if (!pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname !~ '^pg_toast'\n" - " AND n.nspname <> 'information_schema'\n"); + { + appendSystemSchemaFilter(&buf, "c.relnamespace", true); + appendPQExpBufferStr(&buf, " AND n.nspname !~ '^pg_toast'\n"); + } if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "c.relname", NULL, @@ -4673,8 +4669,7 @@ listDomains(const char *pattern, bool verbose, bool showSystem) appendPQExpBufferStr(&buf, "WHERE t.typtype = 'd'\n"); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "t.typnamespace", true); if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "t.typname", NULL, @@ -4752,8 +4747,7 @@ listConversions(const char *pattern, bool verbose, bool showSystem) appendPQExpBufferStr(&buf, "WHERE true\n"); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "c.connamespace", true); if (!validateSQLNamePattern(&buf, pattern, true, false, "n.nspname", "c.conname", NULL, @@ -5223,8 +5217,7 @@ listCollations(const char *pattern, bool verbose, bool showSystem) "WHERE n.oid = c.collnamespace\n"); if (!showSystem && !pattern) - appendPQExpBufferStr(&buf, " AND n.nspname <> 'pg_catalog'\n" - " AND n.nspname <> 'information_schema'\n"); + appendSystemSchemaFilter(&buf, "c.collnamespace", true); /* * Hide collations that aren't usable in the current database's encoding. @@ -6425,6 +6418,25 @@ listOneExtensionContents(const char *extname, const char *oid) return true; } +/* + * Append a filter that excludes objects in pg_catalog and + * information_schema. Use the namespace OID stored in the object's catalog, + * rather than the name obtained through pg_namespace, so the restriction can + * be applied during the object catalog scan. The subquery also tolerates a + * missing information_schema. + */ +static void +appendSystemSchemaFilter(PQExpBuffer buf, const char *namespacevar, + bool have_where) +{ + appendPQExpBuffer(buf, + "%s%s <> ALL (ARRAY(\n" + " SELECT oid FROM pg_catalog.pg_namespace\n" + " WHERE nspname IN ('pg_catalog', 'information_schema')))\n", + have_where ? " AND " : "WHERE ", + namespacevar); +} + /* * validateSQLNamePattern * -- 2.44.0