From 4d8374500d54c7e10d702e94f42c00f13af3773a Mon Sep 17 00:00:00 2001 From: xiaoyu liu Date: Wed, 22 Jul 2026 18:49:53 +0800 Subject: [PATCH v2] 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 the filter construction in a helper and use inner joins for the corresponding object-to-namespace joins. --- src/bin/psql/describe.c | 116 ++++++++++++++++++++++------------------ 1 file changed, 64 insertions(+), 52 deletions(-) diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c index 063e2555814..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, @@ -102,20 +105,19 @@ describeAggregates(const char *pattern, bool verbose, bool showSystem) appendPQExpBuffer(&buf, " pg_catalog.obj_description(p.oid, 'pg_proc') as \"%s\"\n" "FROM pg_catalog.pg_proc p\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace\n" + " JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace\n" "WHERE p.prokind = " CppAsString2(PROKIND_AGGREGATE) "\n", gettext_noop("Description")); else appendPQExpBuffer(&buf, " pg_catalog.obj_description(p.oid, 'pg_proc') as \"%s\"\n" "FROM pg_catalog.pg_proc p\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace\n" + " JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace\n" "WHERE p.proisagg\n", 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, @@ -426,7 +428,7 @@ describeFunctions(const char *functypes, const char *func_pattern, appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_proc p" - "\n LEFT JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace\n"); + "\n JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace\n"); for (int i = 0; i < num_arg_patterns; i++) { @@ -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); @@ -666,7 +670,7 @@ describeTypes(const char *pattern, bool verbose, bool showSystem) gettext_noop("Description")); appendPQExpBufferStr(&buf, "FROM pg_catalog.pg_type t\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace\n"); + " JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace\n"); /* * do not include complex types (typrelid!=0) unless they are standalone @@ -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), @@ -828,7 +831,7 @@ describeOperators(const char *oper_pattern, " coalesce(pg_catalog.obj_description(o.oid, 'pg_operator'),\n" " pg_catalog.obj_description(o.oprcode, 'pg_proc')) AS \"%s\"\n" "FROM pg_catalog.pg_operator o\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = o.oprnamespace\n", + " JOIN pg_catalog.pg_namespace n ON n.oid = o.oprnamespace\n", gettext_noop("Description")); if (num_arg_patterns >= 2) @@ -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, @@ -1121,7 +1123,7 @@ permissionsList(const char *pattern, bool showSystem) gettext_noop("Policies")); appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_class c\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n" + " JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n" "WHERE c.relkind IN (" CppAsString2(RELKIND_RELATION) "," CppAsString2(RELKIND_VIEW) "," @@ -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, @@ -1280,13 +1281,12 @@ objectDescription(const char *pattern, bool showSystem) " FROM pg_catalog.pg_constraint pgc\n" " JOIN pg_catalog.pg_class c " "ON c.oid = pgc.conrelid\n" - " LEFT JOIN pg_catalog.pg_namespace n " + " JOIN pg_catalog.pg_namespace n " " ON n.oid = c.relnamespace\n", 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, @@ -1304,13 +1304,12 @@ objectDescription(const char *pattern, bool showSystem) " FROM pg_catalog.pg_constraint pgc\n" " JOIN pg_catalog.pg_type t " "ON t.oid = pgc.contypid\n" - " LEFT JOIN pg_catalog.pg_namespace n " + " JOIN pg_catalog.pg_namespace n " " ON n.oid = t.typnamespace\n", 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, @@ -1375,13 +1372,12 @@ objectDescription(const char *pattern, bool showSystem) " CAST('%s' AS pg_catalog.text) as object\n" " FROM pg_catalog.pg_rewrite r\n" " JOIN pg_catalog.pg_class c ON c.oid = r.ev_class\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n" + " JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n" " WHERE r.rulename != '_RETURN'\n", 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, @@ -1398,12 +1394,11 @@ objectDescription(const char *pattern, bool showSystem) " CAST('%s' AS pg_catalog.text) as object\n" " FROM pg_catalog.pg_trigger t\n" " JOIN pg_catalog.pg_class c ON c.oid = t.tgrelid\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n", + " JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n", 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, @@ -1462,11 +1457,10 @@ describeTableDetails(const char *pattern, bool verbose, bool showSystem) " n.nspname,\n" " c.relname\n" "FROM pg_catalog.pg_class c\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace\n"); + " 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, @@ -4188,7 +4182,7 @@ listTables(const char *tabtypes, const char *pattern, bool verbose, bool showSys appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_class c" - "\n LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace"); + "\n JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace"); if (pset.sversion >= 120000 && !pset.hide_tableam && (showTables || showMatViews || showIndexes)) @@ -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, @@ -4442,7 +4437,7 @@ listPartitionedTables(const char *reltypes, const char *pattern, bool verbose) appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_class c" - "\n LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace"); + "\n JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace"); if (showIndexes) appendPQExpBufferStr(&buf, @@ -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, @@ -4662,7 +4658,7 @@ listDomains(const char *pattern, bool verbose, bool showSystem) appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_type t\n" - " LEFT JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace\n"); + " JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace\n"); if (verbose) appendPQExpBufferStr(&buf, @@ -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