From 8737bffb55429b77f5dc34b1f9167096cbf18c21 Mon Sep 17 00:00:00 2001
From: Mark Dilger <mark.dilger@enterprisedb.com>
Date: Tue, 5 Apr 2022 16:08:04 -0700
Subject: [PATCH v8] Reject patterns with too many parts or wrong db

Object name patterns used by pg_dump and psql potentially contain
multiple parts (dotted names), and nothing prevents users from
specifying a name with too many parts, nor specifying a
database-qualified name for a database other than the currently
connected database.  Prior to PostgreSQL version 14, pg_dump,
pg_dumpall and psql quietly discarded extra parts of the name on the
left.  For example, `pg_dump -t` only expected a possibly schema
qualified table name, not a database name, and the following command

  pg_dump -t production.marketing.customers

quietly ignored the "production" database name with neither warning
nor error.  Commit 2c8726c4b0a496608919d1f78a5abc8c9b6e0868 changed
the behavior of name parsing.  Where names contain more than the
maximum expected number of dots, the extra dots on the right were
interpreted as part of the name, such that the above example was
interpreted as schema=production, relation=marketing.customers.
This turns out to be highly unintuitive to users.

We've had reports that users sometimes copy-and-paste database- and
schema-qualified relation names from the logs.
https://www.postgresql.org/message-id/20211013165426.GD27491%40telsasoft.com

There is no support for cross database references, but allowing a
database qualified pattern when the database portion matches the
current database, as in the above report, seems more friendly than
rejecting it, so do that.  We don't allow the database portion
itself to be a pattern, because if it matched more than one database
(including the current one), there would be confusion about which
database(s) were processed.

Consistent with how we allow db.schemapat.relpat in pg_dump and psql,
also allow db.schemapat for specifying schemas, as:

    \dn mydb.myschema

in psql and

    pg_dump --schema=mydb.myschema

Fix the pre-v14 behavior of ignoring leading portions of patterns
containing too many dotted names, and the v14.0 misfeature of
combining trailing portions of such patterns, and instead reject
such patterns in all cases by raising an error.
---
 doc/src/sgml/ref/psql-ref.sgml       |  17 +-
 src/bin/pg_amcheck/pg_amcheck.c      |  27 +-
 src/bin/pg_amcheck/t/002_nonesuch.pl |  99 +++++-
 src/bin/pg_dump/pg_dump.c            |  65 +++-
 src/bin/pg_dump/pg_dumpall.c         |  13 +-
 src/bin/pg_dump/t/002_pg_dump.pl     |  53 +++
 src/bin/psql/describe.c              | 502 ++++++++++++++++++---------
 src/fe_utils/string_utils.c          | 123 +++++--
 src/include/fe_utils/string_utils.h  |   6 +-
 src/test/regress/expected/psql.out   | 221 ++++++++++++
 src/test/regress/sql/psql.sql        | 112 ++++++
 11 files changed, 1023 insertions(+), 215 deletions(-)

diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index f01adb1fd2..f82dfc5eb9 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -3622,14 +3622,27 @@ select 1\; select 2\; select 3;
   </para>
 
   <para>
-   A pattern that contains a dot (<literal>.</literal>) is interpreted as a schema
+   A relation pattern that contains a dot (<literal>.</literal>) is interpreted as a schema
    name pattern followed by an object name pattern.  For example,
    <literal>\dt foo*.*bar*</literal> displays all tables whose table name
    includes <literal>bar</literal> that are in schemas whose schema name
    starts with <literal>foo</literal>.  When no dot appears, then the pattern
    matches only objects that are visible in the current schema search path.
    Again, a dot within double quotes loses its special meaning and is matched
-   literally.
+   literally.  A relation pattern that contains two dots (<literal>.</literal>)
+   is interpreted as a database name followed by a schema name pattern followed
+   by an object name pattern.  The database name portion will not be treated as
+   a pattern and must match the name of the currently connected database, else
+   an error will be raised.
+  </para>
+
+  <para>
+   A schema pattern that contains a dot (<literal>.</literal>) is interpreted
+   as a database name followed by a schema name pattern.  For example,
+   <literal>\dn mydb.*foo*</literal> displays all schemas whose schema name
+   includes <literal>foo</literal>.  The database name portion will not be
+   treated as a pattern and must match the name of the currently connected
+   database, else an error will be raised.
   </para>
 
   <para>
diff --git a/src/bin/pg_amcheck/pg_amcheck.c b/src/bin/pg_amcheck/pg_amcheck.c
index 6607f72938..522dccf15a 100644
--- a/src/bin/pg_amcheck/pg_amcheck.c
+++ b/src/bin/pg_amcheck/pg_amcheck.c
@@ -1334,10 +1334,17 @@ static void
 append_database_pattern(PatternInfoArray *pia, const char *pattern, int encoding)
 {
 	PQExpBufferData buf;
+	int			dotcnt;
 	PatternInfo *info = extend_pattern_info_array(pia);
 
 	initPQExpBuffer(&buf);
-	patternToSQLRegex(encoding, NULL, NULL, &buf, pattern, false);
+	patternToSQLRegex(encoding, NULL, NULL, &buf, pattern, false, false,
+					  &dotcnt);
+	if (dotcnt > 0)
+	{
+		pg_log_error("improper qualified name (too many dotted names): %s", pattern);
+		exit(2);
+	}
 	info->pattern = pattern;
 	info->db_regex = pstrdup(buf.data);
 
@@ -1358,12 +1365,19 @@ append_schema_pattern(PatternInfoArray *pia, const char *pattern, int encoding)
 {
 	PQExpBufferData dbbuf;
 	PQExpBufferData nspbuf;
+	int			dotcnt;
 	PatternInfo *info = extend_pattern_info_array(pia);
 
 	initPQExpBuffer(&dbbuf);
 	initPQExpBuffer(&nspbuf);
 
-	patternToSQLRegex(encoding, NULL, &dbbuf, &nspbuf, pattern, false);
+	patternToSQLRegex(encoding, NULL, &dbbuf, &nspbuf, pattern, false, false,
+					  &dotcnt);
+	if (dotcnt > 1)
+	{
+		pg_log_error("improper qualified name (too many dotted names): %s", pattern);
+		exit(2);
+	}
 	info->pattern = pattern;
 	if (dbbuf.data[0])
 	{
@@ -1395,13 +1409,20 @@ append_relation_pattern_helper(PatternInfoArray *pia, const char *pattern,
 	PQExpBufferData dbbuf;
 	PQExpBufferData nspbuf;
 	PQExpBufferData relbuf;
+	int			dotcnt;
 	PatternInfo *info = extend_pattern_info_array(pia);
 
 	initPQExpBuffer(&dbbuf);
 	initPQExpBuffer(&nspbuf);
 	initPQExpBuffer(&relbuf);
 
-	patternToSQLRegex(encoding, &dbbuf, &nspbuf, &relbuf, pattern, false);
+	patternToSQLRegex(encoding, &dbbuf, &nspbuf, &relbuf, pattern, false,
+					  false, &dotcnt);
+	if (dotcnt > 2)
+	{
+		pg_log_error("improper relation name (too many dotted names): %s", pattern);
+		exit(2);
+	}
 	info->pattern = pattern;
 	if (dbbuf.data[0])
 	{
diff --git a/src/bin/pg_amcheck/t/002_nonesuch.pl b/src/bin/pg_amcheck/t/002_nonesuch.pl
index 56d55199f8..6c0f97027d 100644
--- a/src/bin/pg_amcheck/t/002_nonesuch.pl
+++ b/src/bin/pg_amcheck/t/002_nonesuch.pl
@@ -147,6 +147,100 @@ $node->command_checks_all(
 	[qr/pg_amcheck: error: no heap tables to check matching "\."/],
 	'checking table pattern "."');
 
+# Check that a multipart database name is rejected
+$node->command_checks_all(
+	[ 'pg_amcheck', '-d', 'localhost.postgres' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper qualified name \(too many dotted names\): localhost\.postgres/
+	],
+	'multipart database patterns are rejected'
+);
+
+# Check that a three-part schema name is rejected
+$node->command_checks_all(
+	[ 'pg_amcheck', '-s', 'localhost.postgres.pg_catalog' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper qualified name \(too many dotted names\): localhost\.postgres\.pg_catalog/
+	],
+	'three part schema patterns are rejected'
+);
+
+# Check that a four-part table name is rejected
+$node->command_checks_all(
+	[ 'pg_amcheck', '-t', 'localhost.postgres.pg_catalog.pg_class' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper relation name \(too many dotted names\): localhost\.postgres\.pg_catalog\.pg_class/
+	],
+	'four part table patterns are rejected'
+);
+
+# Check that too many dotted names still draws an error under --no-strict-names
+# That flag means that it is ok for the object to be missing, not that it is ok
+# for the object name to be ungrammatical
+$node->command_checks_all(
+	[ 'pg_amcheck', '--no-strict-names', '-t', 'this.is.a.really.long.dotted.string' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper relation name \(too many dotted names\): this\.is\.a\.really\.long\.dotted\.string/
+	],
+	'ungrammatical table names still draw errors under --no-strict-names'
+);
+$node->command_checks_all(
+	[ 'pg_amcheck', '--no-strict-names', '-s', 'postgres.long.dotted.string' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper qualified name \(too many dotted names\): postgres\.long\.dotted\.string/
+	],
+	'ungrammatical schema names still draw errors under --no-strict-names'
+);
+$node->command_checks_all(
+	[ 'pg_amcheck', '--no-strict-names', '-d', 'postgres.long.dotted.string' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper qualified name \(too many dotted names\): postgres\.long\.dotted\.string/
+	],
+	'ungrammatical database names still draw errors under --no-strict-names'
+);
+
+# Likewise for exclusion patterns
+$node->command_checks_all(
+	[ 'pg_amcheck', '--no-strict-names', '-T', 'a.b.c.d' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper relation name \(too many dotted names\): a\.b\.c\.d/
+	],
+	'ungrammatical table exclusions still draw errors under --no-strict-names'
+);
+$node->command_checks_all(
+	[ 'pg_amcheck', '--no-strict-names', '-S', 'a.b.c' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper qualified name \(too many dotted names\): a\.b\.c/
+	],
+	'ungrammatical schema exclusions still draw errors under --no-strict-names'
+);
+$node->command_checks_all(
+	[ 'pg_amcheck', '--no-strict-names', '-D', 'a.b' ],
+	2,
+	[qr/^$/],
+	[
+		qr/pg_amcheck: error: improper qualified name \(too many dotted names\): a\.b/
+	],
+	'ungrammatical database exclusions still draw errors under --no-strict-names'
+);
+
+
 #########################################
 # Test checking non-existent databases, schemas, tables, and indexes
 
@@ -165,9 +259,7 @@ $node->command_checks_all(
 		'-d',         'no*such*database',
 		'-r',         'none.none',
 		'-r',         'none.none.none',
-		'-r',         'this.is.a.really.long.dotted.string',
 		'-r',         'postgres.none.none',
-		'-r',         'postgres.long.dotted.string',
 		'-r',         'postgres.pg_catalog.none',
 		'-r',         'postgres.none.pg_class',
 		'-t',         'postgres.pg_catalog.pg_class',          # This exists
@@ -186,15 +278,12 @@ $node->command_checks_all(
 		qr/pg_amcheck: warning: no connectable databases to check matching "no\*such\*database"/,
 		qr/pg_amcheck: warning: no relations to check matching "none\.none"/,
 		qr/pg_amcheck: warning: no connectable databases to check matching "none\.none\.none"/,
-		qr/pg_amcheck: warning: no connectable databases to check matching "this\.is\.a\.really\.long\.dotted\.string"/,
 		qr/pg_amcheck: warning: no relations to check matching "postgres\.none\.none"/,
-		qr/pg_amcheck: warning: no relations to check matching "postgres\.long\.dotted\.string"/,
 		qr/pg_amcheck: warning: no relations to check matching "postgres\.pg_catalog\.none"/,
 		qr/pg_amcheck: warning: no relations to check matching "postgres\.none\.pg_class"/,
 		qr/pg_amcheck: warning: no connectable databases to check matching "no_such_database"/,
 		qr/pg_amcheck: warning: no connectable databases to check matching "no\*such\*database"/,
 		qr/pg_amcheck: warning: no connectable databases to check matching "none\.none\.none"/,
-		qr/pg_amcheck: warning: no connectable databases to check matching "this\.is\.a\.really\.long\.dotted\.string"/,
 	],
 	'many unmatched patterns and one matched pattern under --no-strict-names'
 );
diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 535b160165..c191f36730 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -178,6 +178,9 @@ static void expand_table_name_patterns(Archive *fout,
 									   SimpleStringList *patterns,
 									   SimpleOidList *oids,
 									   bool strict_names);
+static void prohibit_crossdb_refs(PGconn *conn, const char *dbname,
+								  const char *pattern);
+
 static NamespaceInfo *findNamespace(Oid nsoid);
 static void dumpTableData(Archive *fout, const TableDataInfo *tdinfo);
 static void refreshMatViewData(Archive *fout, const TableDataInfo *tdinfo);
@@ -1321,10 +1324,21 @@ expand_schema_name_patterns(Archive *fout,
 
 	for (cell = patterns->head; cell; cell = cell->next)
 	{
+		PQExpBufferData	dbbuf;
+		int		dotcnt;
+
 		appendPQExpBufferStr(query,
 							 "SELECT oid FROM pg_catalog.pg_namespace n\n");
+		initPQExpBuffer(&dbbuf);
 		processSQLNamePattern(GetConnection(fout), query, cell->val, false,
-							  false, NULL, "n.nspname", NULL, NULL);
+							  false, NULL, "n.nspname", NULL, NULL, &dbbuf,
+							  &dotcnt);
+		if (dotcnt > 1)
+			fatal("improper qualified name (too many dotted names): %s",
+				  cell->val);
+		else if (dotcnt == 1)
+			prohibit_crossdb_refs(GetConnection(fout), dbbuf.data, cell->val);
+		termPQExpBuffer(&dbbuf);
 
 		res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 		if (strict_names && PQntuples(res) == 0)
@@ -1368,10 +1382,16 @@ expand_extension_name_patterns(Archive *fout,
 	 */
 	for (cell = patterns->head; cell; cell = cell->next)
 	{
+		int		dotcnt;
+
 		appendPQExpBufferStr(query,
 							 "SELECT oid FROM pg_catalog.pg_extension e\n");
 		processSQLNamePattern(GetConnection(fout), query, cell->val, false,
-							  false, NULL, "e.extname", NULL, NULL);
+							  false, NULL, "e.extname", NULL, NULL, NULL,
+							  &dotcnt);
+		if (dotcnt > 0)
+			fatal("improper qualified name (too many dotted names): %s",
+				  cell->val);
 
 		res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 		if (strict_names && PQntuples(res) == 0)
@@ -1415,10 +1435,16 @@ expand_foreign_server_name_patterns(Archive *fout,
 
 	for (cell = patterns->head; cell; cell = cell->next)
 	{
+		int		dotcnt;
+
 		appendPQExpBufferStr(query,
 							 "SELECT oid FROM pg_catalog.pg_foreign_server s\n");
 		processSQLNamePattern(GetConnection(fout), query, cell->val, false,
-							  false, NULL, "s.srvname", NULL, NULL);
+							  false, NULL, "s.srvname", NULL, NULL, NULL,
+							  &dotcnt);
+		if (dotcnt > 0)
+			fatal("improper qualified name (too many dotted names): %s",
+				  cell->val);
 
 		res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 		if (PQntuples(res) == 0)
@@ -1461,6 +1487,9 @@ expand_table_name_patterns(Archive *fout,
 
 	for (cell = patterns->head; cell; cell = cell->next)
 	{
+		PQExpBufferData	dbbuf;
+		int		dotcnt;
+
 		/*
 		 * Query must remain ABSOLUTELY devoid of unqualified names.  This
 		 * would be unnecessary given a pg_table_is_visible() variant taking a
@@ -1476,9 +1505,17 @@ expand_table_name_patterns(Archive *fout,
 						  RELKIND_RELATION, RELKIND_SEQUENCE, RELKIND_VIEW,
 						  RELKIND_MATVIEW, RELKIND_FOREIGN_TABLE,
 						  RELKIND_PARTITIONED_TABLE);
+		initPQExpBuffer(&dbbuf);
 		processSQLNamePattern(GetConnection(fout), query, cell->val, true,
 							  false, "n.nspname", "c.relname", NULL,
-							  "pg_catalog.pg_table_is_visible(c.oid)");
+							  "pg_catalog.pg_table_is_visible(c.oid)", &dbbuf,
+							  &dotcnt);
+		if (dotcnt > 2)
+			fatal("improper relation name (too many dotted names): %s",
+				  cell->val);
+		else if (dotcnt == 2)
+			prohibit_crossdb_refs(GetConnection(fout), dbbuf.data, cell->val);
+		termPQExpBuffer(&dbbuf);
 
 		ExecuteSqlStatement(fout, "RESET search_path");
 		res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
@@ -1499,6 +1536,26 @@ expand_table_name_patterns(Archive *fout,
 	destroyPQExpBuffer(query);
 }
 
+/*
+ * Verifies that the connected database name matches the given database name,
+ * and if not, dies with an error about the given pattern.
+ *
+ * The 'dbname' argument should be a literal name parsed from 'pattern'.
+ */
+static void
+prohibit_crossdb_refs(PGconn *conn, const char *dbname, const char *pattern)
+{
+	const char *db;
+
+	db = PQdb(conn);
+	if (db == NULL)
+		fatal("You are currently not connected to a database.");
+
+	if (strcmp(db, dbname) != 0)
+		fatal("cross-database references are not implemented: %s",
+			  pattern);
+}
+
 /*
  * checkExtensionMembership
  *		Determine whether object is an extension member, and if so,
diff --git a/src/bin/pg_dump/pg_dumpall.c b/src/bin/pg_dump/pg_dumpall.c
index 9c9f7c6d63..c35fb05ee5 100644
--- a/src/bin/pg_dump/pg_dumpall.c
+++ b/src/bin/pg_dump/pg_dumpall.c
@@ -1226,10 +1226,21 @@ expand_dbname_patterns(PGconn *conn,
 
 	for (SimpleStringListCell *cell = patterns->head; cell; cell = cell->next)
 	{
+		int		dotcnt;
+
 		appendPQExpBufferStr(query,
 							 "SELECT datname FROM pg_catalog.pg_database n\n");
 		processSQLNamePattern(conn, query, cell->val, false,
-							  false, NULL, "datname", NULL, NULL);
+							  false, NULL, "datname", NULL, NULL, NULL,
+							  &dotcnt);
+
+		if (dotcnt > 0)
+		{
+			pg_log_error("improper qualified name (too many dotted names): %s",
+						 cell->val);
+			PQfinish(conn);
+			exit_nicely(1);
+		}
 
 		res = executeQuery(conn, query->data);
 		for (int i = 0; i < PQntuples(res); i++)
diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl
index 75b754a420..e72c163dab 100644
--- a/src/bin/pg_dump/t/002_pg_dump.pl
+++ b/src/bin/pg_dump/t/002_pg_dump.pl
@@ -4005,6 +4005,59 @@ command_fails_like(
 	qr/\Qpg_dump: error: no matching tables were found for pattern\E/,
 	'no matching tables');
 
+#########################################
+# Test invalid multipart database names
+
+$node->command_fails_like(
+	[ 'pg_dumpall', '--exclude-database', 'myhost.mydb' ],
+	qr/pg_dumpall: error: improper qualified name \(too many dotted names\): myhost\.mydb/,
+	'pg_dumpall: option --exclude-database rejects multipart database names'
+);
+
+#########################################
+# Test valid database exclusion patterns
+$node->command_ok(
+	[ 'pg_dumpall', '--exclude-database', '??*' ],
+	'pg_dumpall: option --exclude-database handles database name patterns'
+);
+
+
+#########################################
+# Test invalid multipart schema names
+
+$node->command_fails_like(
+	[ 'pg_dump', '--schema', 'myhost.mydb.myschema' ],
+	qr/pg_dump: error: improper qualified name \(too many dotted names\): myhost\.mydb\.myschema/,
+	'pg_dump: option --schema rejects three-part schema names'
+);
+
+$node->command_fails_like(
+	[ 'pg_dump', '--schema', 'otherdb.myschema' ],
+	qr/pg_dump: error: cross-database references are not implemented: otherdb\.myschema/,
+	'pg_dump: option --schema rejects cross-database multipart schema names'
+);
+
+$node->command_fails_like(
+	[ 'pg_dump', '--schema', 'otherdb.myschema' ],
+	qr/pg_dump: error: cross-database references are not implemented: otherdb\.myschema/,
+	'pg_dump: option --schema rejects cross-database multipart schema names'
+);
+
+#########################################
+# Test invalid multipart relation names
+
+$node->command_fails_like(
+	[ 'pg_dump', '--table', 'myhost.mydb.myschema.mytable' ],
+	qr/pg_dump: error: improper relation name \(too many dotted names\): myhost\.mydb\.myschema\.mytable/,
+	'pg_dump: option --table rejects four-part table names'
+);
+
+$node->command_fails_like(
+	[ 'pg_dump', '--table', 'otherdb.pg_catalog.pg_class' ],
+	qr/pg_dump: error: cross-database references are not implemented: otherdb\.pg_catalog\.pg_class/,
+	'pg_dump: option --table rejects cross-database three part table names'
+);
+
 #########################################
 # Run all runs
 
diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index 4dddf08789..6a699912cf 100644
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -46,6 +46,12 @@ 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 bool validateSQLNamePattern(PQExpBuffer buf, const char *pattern,
+								   bool have_where, bool force_escape,
+								   const char *schemavar, const char *namevar,
+								   const char *altnamevar,
+								   const char *visibilityrule,
+								   bool *added_clause, int maxparts);
 
 
 /*----------------
@@ -102,9 +108,11 @@ describeAggregates(const char *pattern, bool verbose, bool showSystem)
 		appendPQExpBufferStr(&buf, "      AND n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "p.proname", NULL,
-						  "pg_catalog.pg_function_is_visible(p.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+							  "n.nspname", "p.proname", NULL,
+							  "pg_catalog.pg_function_is_visible(p.oid)",
+							  NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2, 4;");
 
@@ -170,9 +178,11 @@ describeAccessMethods(const char *pattern, bool verbose)
 	appendPQExpBufferStr(&buf,
 						 "\nFROM pg_catalog.pg_am\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "amname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "amname", NULL,
+								NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -230,9 +240,11 @@ describeTablespaces(const char *pattern, bool verbose)
 	appendPQExpBufferStr(&buf,
 						 "\nFROM pg_catalog.pg_tablespace\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "spcname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "spcname", NULL,
+								NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -518,9 +530,11 @@ describeFunctions(const char *functypes, const char *func_pattern,
 		appendPQExpBufferStr(&buf, "      )\n");
 	}
 
-	processSQLNamePattern(pset.db, &buf, func_pattern, have_where, false,
-						  "n.nspname", "p.proname", NULL,
-						  "pg_catalog.pg_function_is_visible(p.oid)");
+	if (!validateSQLNamePattern(&buf, func_pattern, have_where, false,
+								"n.nspname", "p.proname", NULL,
+								"pg_catalog.pg_function_is_visible(p.oid)",
+								NULL, 3))
+		return false;
 
 	for (int i = 0; i < num_arg_patterns; i++)
 	{
@@ -542,10 +556,12 @@ describeFunctions(const char *functypes, const char *func_pattern,
 					 "pg_catalog.format_type(t%d.oid, NULL)", i);
 			snprintf(tiv, sizeof(tiv),
 					 "pg_catalog.pg_type_is_visible(t%d.oid)", i);
-			processSQLNamePattern(pset.db, &buf,
-								  map_typename_pattern(arg_patterns[i]),
-								  true, false,
-								  nspname, typname, ft, tiv);
+			if (!validateSQLNamePattern(&buf,
+										map_typename_pattern(arg_patterns[i]),
+										true, false,
+										nspname, typname, ft, tiv,
+										NULL, 3))
+				return false;
 		}
 		else
 		{
@@ -660,11 +676,13 @@ describeTypes(const char *pattern, bool verbose, bool showSystem)
 							 "      AND n.nspname <> 'information_schema'\n");
 
 	/* Match name pattern against either internal or external name */
-	processSQLNamePattern(pset.db, &buf, map_typename_pattern(pattern),
-						  true, false,
-						  "n.nspname", "t.typname",
-						  "pg_catalog.format_type(t.oid, NULL)",
-						  "pg_catalog.pg_type_is_visible(t.oid)");
+	if (!validateSQLNamePattern(&buf, map_typename_pattern(pattern),
+								true, false,
+								"n.nspname", "t.typname",
+								"pg_catalog.format_type(t.oid, NULL)",
+								"pg_catalog.pg_type_is_visible(t.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -813,10 +831,12 @@ describeOperators(const char *oper_pattern,
 		appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, oper_pattern,
-						  !showSystem && !oper_pattern, true,
-						  "n.nspname", "o.oprname", NULL,
-						  "pg_catalog.pg_operator_is_visible(o.oid)");
+	if (!validateSQLNamePattern(&buf, oper_pattern,
+								!showSystem && !oper_pattern, true,
+								"n.nspname", "o.oprname", NULL,
+								"pg_catalog.pg_operator_is_visible(o.oid)",
+								NULL, 3))
+		return false;
 
 	if (num_arg_patterns == 1)
 		appendPQExpBufferStr(&buf, "  AND o.oprleft = 0\n");
@@ -841,10 +861,12 @@ describeOperators(const char *oper_pattern,
 					 "pg_catalog.format_type(t%d.oid, NULL)", i);
 			snprintf(tiv, sizeof(tiv),
 					 "pg_catalog.pg_type_is_visible(t%d.oid)", i);
-			processSQLNamePattern(pset.db, &buf,
-								  map_typename_pattern(arg_patterns[i]),
-								  true, false,
-								  nspname, typname, ft, tiv);
+			if (!validateSQLNamePattern(&buf,
+										map_typename_pattern(arg_patterns[i]),
+										true, false,
+										nspname, typname, ft, tiv,
+										NULL, 3))
+				return false;
 		}
 		else
 		{
@@ -928,8 +950,10 @@ listAllDbs(const char *pattern, bool verbose)
 							 "  JOIN pg_catalog.pg_tablespace t on d.dattablespace = t.oid\n");
 
 	if (pattern)
-		processSQLNamePattern(pset.db, &buf, pattern, false, false,
-							  NULL, "d.datname", NULL, NULL);
+		if (!validateSQLNamePattern(&buf, pattern, false, false,
+									NULL, "d.datname", NULL, NULL,
+									NULL, 1))
+			return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 	res = PSQLexec(buf.data);
@@ -1078,9 +1102,11 @@ permissionsList(const char *pattern)
 	 * point of view.  You can see 'em by explicit request though, eg with \z
 	 * pg_catalog.*
 	 */
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "c.relname", NULL,
-						  "n.nspname !~ '^pg_' AND pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "c.relname", NULL,
+								"n.nspname !~ '^pg_' AND pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -1145,11 +1171,13 @@ listDefaultACLs(const char *pattern)
 	appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_default_acl d\n"
 						 "     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = d.defaclnamespace\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL,
-						  "n.nspname",
-						  "pg_catalog.pg_get_userbyid(d.defaclrole)",
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL,
+								"n.nspname",
+								"pg_catalog.pg_get_userbyid(d.defaclrole)",
+								NULL,
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2, 3;");
 
@@ -1221,9 +1249,11 @@ objectDescription(const char *pattern, bool showSystem)
 		appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, !showSystem && !pattern,
-						  false, "n.nspname", "pgc.conname", NULL,
-						  "pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern,
+								false, "n.nspname", "pgc.conname", NULL,
+								"pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	/* Domain constraint descriptions */
 	appendPQExpBuffer(&buf,
@@ -1243,9 +1273,11 @@ objectDescription(const char *pattern, bool showSystem)
 		appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, !showSystem && !pattern,
-						  false, "n.nspname", "pgc.conname", NULL,
-						  "pg_catalog.pg_type_is_visible(t.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern,
+								false, "n.nspname", "pgc.conname", NULL,
+								"pg_catalog.pg_type_is_visible(t.oid)",
+								NULL, 3))
+		return false;
 
 	/* Operator class descriptions */
 	appendPQExpBuffer(&buf,
@@ -1265,9 +1297,11 @@ objectDescription(const char *pattern, bool showSystem)
 		appendPQExpBufferStr(&buf, "      AND n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "o.opcname", NULL,
-						  "pg_catalog.pg_opclass_is_visible(o.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "o.opcname", NULL,
+								"pg_catalog.pg_opclass_is_visible(o.oid)",
+								NULL, 3))
+		return false;
 
 	/* Operator family descriptions */
 	appendPQExpBuffer(&buf,
@@ -1287,9 +1321,11 @@ objectDescription(const char *pattern, bool showSystem)
 		appendPQExpBufferStr(&buf, "      AND n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "opf.opfname", NULL,
-						  "pg_catalog.pg_opfamily_is_visible(opf.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "opf.opfname", NULL,
+								"pg_catalog.pg_opfamily_is_visible(opf.oid)",
+								NULL, 3))
+		return false;
 
 	/* Rule descriptions (ignore rules for views) */
 	appendPQExpBuffer(&buf,
@@ -1308,9 +1344,11 @@ objectDescription(const char *pattern, bool showSystem)
 		appendPQExpBufferStr(&buf, "      AND n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "r.rulename", NULL,
-						  "pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "r.rulename", NULL,
+								"pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	/* Trigger descriptions */
 	appendPQExpBuffer(&buf,
@@ -1328,9 +1366,11 @@ objectDescription(const char *pattern, bool showSystem)
 		appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, !showSystem && !pattern, false,
-						  "n.nspname", "t.tgname", NULL,
-						  "pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern, false,
+								"n.nspname", "t.tgname", NULL,
+								"pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf,
 						 ") AS tt\n"
@@ -1384,9 +1424,11 @@ describeTableDetails(const char *pattern, bool verbose, bool showSystem)
 		appendPQExpBufferStr(&buf, "WHERE n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, !showSystem && !pattern, false,
-						  "n.nspname", "c.relname", NULL,
-						  "pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, !showSystem && !pattern, false,
+								"n.nspname", "c.relname", NULL,
+								"pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 2, 3;");
 
@@ -3640,8 +3682,10 @@ describeRoles(const char *pattern, bool verbose, bool showSystem)
 	if (!showSystem && !pattern)
 		appendPQExpBufferStr(&buf, "WHERE r.rolname !~ '^pg_'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "r.rolname", NULL, NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "r.rolname", NULL, NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -3764,10 +3808,13 @@ listDbRoleSettings(const char *pattern, const char *pattern2)
 					  gettext_noop("Role"),
 					  gettext_noop("Database"),
 					  gettext_noop("Settings"));
-	havewhere = processSQLNamePattern(pset.db, &buf, pattern, false, false,
-									  NULL, "r.rolname", NULL, NULL);
-	processSQLNamePattern(pset.db, &buf, pattern2, havewhere, false,
-						  NULL, "d.datname", NULL, NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "r.rolname", NULL, NULL, &havewhere, 1))
+		return false;
+	if (!validateSQLNamePattern(&buf, pattern2, havewhere, false,
+								NULL, "d.datname", NULL, NULL,
+								NULL, 1))
+		return false;
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
 	res = PSQLexec(buf.data);
@@ -3960,9 +4007,11 @@ listTables(const char *tabtypes, const char *pattern, bool verbose, bool showSys
 							 "      AND n.nspname !~ '^pg_toast'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "c.relname", NULL,
-						  "pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "c.relname", NULL,
+								"pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1,2;");
 
@@ -4175,9 +4224,11 @@ listPartitionedTables(const char *reltypes, const char *pattern, bool verbose)
 							 "      AND n.nspname !~ '^pg_toast'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "c.relname", NULL,
-						  "pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "c.relname", NULL,
+								"pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBuffer(&buf, "ORDER BY \"Schema\", %s%s\"Name\";",
 					  mixed_output ? "\"Type\" DESC, " : "",
@@ -4250,8 +4301,10 @@ listLanguages(const char *pattern, bool verbose, bool showSystem)
 					  gettext_noop("Description"));
 
 	if (pattern)
-		processSQLNamePattern(pset.db, &buf, pattern, false, false,
-							  NULL, "l.lanname", NULL, NULL);
+		if (!validateSQLNamePattern(&buf, pattern, false, false,
+									NULL, "l.lanname", NULL, NULL,
+									NULL, 2))
+			return false;
 
 	if (!showSystem && !pattern)
 		appendPQExpBufferStr(&buf, "WHERE l.lanplcallfoid != 0\n");
@@ -4333,9 +4386,11 @@ listDomains(const char *pattern, bool verbose, bool showSystem)
 		appendPQExpBufferStr(&buf, "      AND n.nspname <> 'pg_catalog'\n"
 							 "      AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "t.typname", NULL,
-						  "pg_catalog.pg_type_is_visible(t.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "t.typname", NULL,
+								"pg_catalog.pg_type_is_visible(t.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -4407,9 +4462,11 @@ listConversions(const char *pattern, bool verbose, bool showSystem)
 		appendPQExpBufferStr(&buf, "  AND n.nspname <> 'pg_catalog'\n"
 							 "  AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "c.conname", NULL,
-						  "pg_catalog.pg_conversion_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "c.conname", NULL,
+								"pg_catalog.pg_conversion_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -4484,8 +4541,10 @@ listEventTriggers(const char *pattern, bool verbose)
 	appendPQExpBufferStr(&buf,
 						 "\nFROM pg_catalog.pg_event_trigger e ");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "evtname", NULL, NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "evtname", NULL, NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1");
 
@@ -4576,10 +4635,12 @@ listExtendedStats(const char *pattern)
 	appendPQExpBufferStr(&buf,
 						 " \nFROM pg_catalog.pg_statistic_ext es \n");
 
-	processSQLNamePattern(pset.db, &buf, pattern,
-						  false, false,
-						  "es.stxnamespace::pg_catalog.regnamespace::pg_catalog.text", "es.stxname",
-						  NULL, "pg_catalog.pg_statistics_obj_is_visible(es.oid)");
+	if (!validateSQLNamePattern(&buf, pattern,
+								false, false,
+								"es.stxnamespace::pg_catalog.regnamespace::pg_catalog.text", "es.stxname",
+								NULL, "pg_catalog.pg_statistics_obj_is_visible(es.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -4678,17 +4739,21 @@ listCasts(const char *pattern, bool verbose)
 	 * Match name pattern against either internal or external name of either
 	 * castsource or casttarget
 	 */
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "ns.nspname", "ts.typname",
-						  "pg_catalog.format_type(ts.oid, NULL)",
-						  "pg_catalog.pg_type_is_visible(ts.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"ns.nspname", "ts.typname",
+								"pg_catalog.format_type(ts.oid, NULL)",
+								"pg_catalog.pg_type_is_visible(ts.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, ") OR (true");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "nt.nspname", "tt.typname",
-						  "pg_catalog.format_type(tt.oid, NULL)",
-						  "pg_catalog.pg_type_is_visible(tt.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"nt.nspname", "tt.typname",
+								"pg_catalog.format_type(tt.oid, NULL)",
+								"pg_catalog.pg_type_is_visible(tt.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, ") )\nORDER BY 1, 2;");
 
@@ -4784,9 +4849,11 @@ listCollations(const char *pattern, bool verbose, bool showSystem)
 	 */
 	appendPQExpBufferStr(&buf, "      AND c.collencoding IN (-1, pg_catalog.pg_char_to_encoding(pg_catalog.getdatabaseencoding()))\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "c.collname", NULL,
-						  "pg_catalog.pg_collation_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "c.collname", NULL,
+								"pg_catalog.pg_collation_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -4844,10 +4911,12 @@ listSchemas(const char *pattern, bool verbose, bool showSystem)
 		appendPQExpBufferStr(&buf,
 							 "WHERE n.nspname !~ '^pg_' AND n.nspname <> 'information_schema'\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern,
-						  !showSystem && !pattern, false,
-						  NULL, "n.nspname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern,
+								!showSystem && !pattern, false,
+								NULL, "n.nspname", NULL,
+								NULL,
+								NULL, 2))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -4959,9 +5028,11 @@ listTSParsers(const char *pattern, bool verbose)
 					  gettext_noop("Description")
 		);
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  "n.nspname", "p.prsname", NULL,
-						  "pg_catalog.pg_ts_parser_is_visible(p.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								"n.nspname", "p.prsname", NULL,
+								"pg_catalog.pg_ts_parser_is_visible(p.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -5000,9 +5071,11 @@ listTSParsersVerbose(const char *pattern)
 					  "LEFT JOIN pg_catalog.pg_namespace n ON n.oid = p.prsnamespace\n"
 		);
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  "n.nspname", "p.prsname", NULL,
-						  "pg_catalog.pg_ts_parser_is_visible(p.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								"n.nspname", "p.prsname", NULL,
+								"pg_catalog.pg_ts_parser_is_visible(p.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -5207,9 +5280,11 @@ listTSDictionaries(const char *pattern, bool verbose)
 	appendPQExpBufferStr(&buf, "FROM pg_catalog.pg_ts_dict d\n"
 						 "LEFT JOIN pg_catalog.pg_namespace n ON n.oid = d.dictnamespace\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  "n.nspname", "d.dictname", NULL,
-						  "pg_catalog.pg_ts_dict_is_visible(d.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								"n.nspname", "d.dictname", NULL,
+								"pg_catalog.pg_ts_dict_is_visible(d.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -5268,9 +5343,11 @@ listTSTemplates(const char *pattern, bool verbose)
 	appendPQExpBufferStr(&buf, "FROM pg_catalog.pg_ts_template t\n"
 						 "LEFT JOIN pg_catalog.pg_namespace n ON n.oid = t.tmplnamespace\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  "n.nspname", "t.tmplname", NULL,
-						  "pg_catalog.pg_ts_template_is_visible(t.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								"n.nspname", "t.tmplname", NULL,
+								"pg_catalog.pg_ts_template_is_visible(t.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -5318,9 +5395,11 @@ listTSConfigs(const char *pattern, bool verbose)
 					  gettext_noop("Description")
 		);
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  "n.nspname", "c.cfgname", NULL,
-						  "pg_catalog.pg_ts_config_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								"n.nspname", "c.cfgname", NULL,
+								"pg_catalog.pg_ts_config_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -5360,9 +5439,11 @@ listTSConfigsVerbose(const char *pattern)
 					  "WHERE  p.oid = c.cfgparser\n"
 		);
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  "n.nspname", "c.cfgname", NULL,
-						  "pg_catalog.pg_ts_config_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								"n.nspname", "c.cfgname", NULL,
+								"pg_catalog.pg_ts_config_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 3, 2;");
 
@@ -5532,8 +5613,10 @@ listForeignDataWrappers(const char *pattern, bool verbose)
 							 "       ON d.classoid = fdw.tableoid "
 							 "AND d.objoid = fdw.oid AND d.objsubid = 0\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "fdwname", NULL, NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "fdwname", NULL, NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -5604,8 +5687,10 @@ listForeignServers(const char *pattern, bool verbose)
 							 "ON d.classoid = s.tableoid AND d.objoid = s.oid "
 							 "AND d.objsubid = 0\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "s.srvname", NULL, NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "s.srvname", NULL, NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -5655,8 +5740,10 @@ listUserMappings(const char *pattern, bool verbose)
 
 	appendPQExpBufferStr(&buf, "\nFROM pg_catalog.pg_user_mappings um\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "um.srvname", "um.usename", NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "um.srvname", "um.usename", NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -5722,9 +5809,11 @@ listForeignTables(const char *pattern, bool verbose)
 							 "          ON d.classoid = c.tableoid AND "
 							 "d.objoid = c.oid AND d.objsubid = 0\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  "n.nspname", "c.relname", NULL,
-						  "pg_catalog.pg_table_is_visible(c.oid)");
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								"n.nspname", "c.relname", NULL,
+								"pg_catalog.pg_table_is_visible(c.oid)",
+								NULL, 3))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2;");
 
@@ -5768,10 +5857,12 @@ listExtensions(const char *pattern)
 					  gettext_noop("Schema"),
 					  gettext_noop("Description"));
 
-	processSQLNamePattern(pset.db, &buf, pattern,
-						  false, false,
-						  NULL, "e.extname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern,
+								false, false,
+								NULL, "e.extname", NULL,
+								NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -5807,10 +5898,12 @@ listExtensionContents(const char *pattern)
 					  "SELECT e.extname, e.oid\n"
 					  "FROM pg_catalog.pg_extension e\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern,
-						  false, false,
-						  NULL, "e.extname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern,
+								false, false,
+								NULL, "e.extname", NULL,
+								NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -5892,6 +5985,59 @@ listOneExtensionContents(const char *extname, const char *oid)
 	return true;
 }
 
+/*
+ * validateSQLNamePattern
+ *
+ * Wrapper around string_utils's processSQLNamePattern which also checks the
+ * pattern's validity.  In addition to that function's parameters, takes a
+ * 'maxparts' parameter specifying the maximum number of dotted names the
+ * pattern is allowed to have, and a 'added_clause' parameter that returns by
+ * reference whether a clause was added to 'buf'.  Returns whether the pattern
+ * passed validation, after logging any errors.
+ */
+static bool
+validateSQLNamePattern(PQExpBuffer buf, const char *pattern, bool have_where,
+					   bool force_escape, const char *schemavar,
+					   const char *namevar, const char *altnamevar,
+					   const char *visibilityrule, bool *added_clause,
+					   int maxparts)
+{
+	PQExpBufferData	dbbuf;
+	int			dotcnt;
+	bool		added;
+
+	initPQExpBuffer(&dbbuf);
+	added = processSQLNamePattern(pset.db, buf, pattern, have_where, force_escape,
+								  schemavar, namevar, altnamevar,
+								  visibilityrule, &dbbuf, &dotcnt);
+	if (added_clause != NULL)
+		*added_clause = added;
+
+	if (dotcnt >= maxparts)
+	{
+		pg_log_error("improper qualified name (too many dotted names): %s",
+					 pattern);
+		termPQExpBuffer(&dbbuf);
+		return false;
+	}
+
+	if (maxparts > 1 && dotcnt == maxparts-1)
+	{
+		if (PQdb(pset.db) == NULL)
+		{
+			pg_log_error("You are currently not connected to a database.");
+			return false;
+		}
+		if (strcmp(PQdb(pset.db), dbbuf.data) != 0)
+		{
+			pg_log_error("cross-database references are not implemented: %s",
+						 pattern);
+			return false;
+		}
+	}
+	return true;
+}
+
 /*
  * \dRp
  * Lists publications.
@@ -5965,9 +6111,11 @@ listPublications(const char *pattern)
 	appendPQExpBufferStr(&buf,
 						 "\nFROM pg_catalog.pg_publication\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "pubname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "pubname", NULL,
+								NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -6085,9 +6233,11 @@ describePublications(const char *pattern)
 	appendPQExpBufferStr(&buf,
 						 "\nFROM pg_catalog.pg_publication\n");
 
-	processSQLNamePattern(pset.db, &buf, pattern, false, false,
-						  NULL, "pubname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern, false, false,
+								NULL, "pubname", NULL,
+								NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 2;");
 
@@ -6342,9 +6492,11 @@ describeSubscriptions(const char *pattern, bool verbose)
 						 "                 FROM pg_catalog.pg_database\n"
 						 "                 WHERE datname = pg_catalog.current_database())");
 
-	processSQLNamePattern(pset.db, &buf, pattern, true, false,
-						  NULL, "subname", NULL,
-						  NULL);
+	if (!validateSQLNamePattern(&buf, pattern, true, false,
+								NULL, "subname", NULL,
+								NULL,
+								NULL, 1))
+		return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1;");
 
@@ -6445,15 +6597,19 @@ listOperatorClasses(const char *access_method_pattern,
 							 "  LEFT JOIN pg_catalog.pg_namespace ofn ON ofn.oid = of.opfnamespace\n");
 
 	if (access_method_pattern)
-		have_where = processSQLNamePattern(pset.db, &buf, access_method_pattern,
-										   false, false, NULL, "am.amname", NULL, NULL);
+		if (!validateSQLNamePattern(&buf, access_method_pattern,
+									false, false, NULL, "am.amname", NULL, NULL,
+									&have_where, 1))
+			return false;
 	if (type_pattern)
 	{
 		/* Match type name pattern against either internal or external name */
-		processSQLNamePattern(pset.db, &buf, type_pattern, have_where, false,
-							  "tn.nspname", "t.typname",
-							  "pg_catalog.format_type(t.oid, NULL)",
-							  "pg_catalog.pg_type_is_visible(t.oid)");
+		if (!validateSQLNamePattern(&buf, type_pattern, have_where, false,
+									"tn.nspname", "t.typname",
+									"pg_catalog.format_type(t.oid, NULL)",
+									"pg_catalog.pg_type_is_visible(t.oid)",
+									NULL, 3))
+			return false;
 	}
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2, 4;");
@@ -6517,8 +6673,10 @@ listOperatorFamilies(const char *access_method_pattern,
 						 "  LEFT JOIN pg_catalog.pg_namespace n ON n.oid = f.opfnamespace\n");
 
 	if (access_method_pattern)
-		have_where = processSQLNamePattern(pset.db, &buf, access_method_pattern,
-										   false, false, NULL, "am.amname", NULL, NULL);
+		if (!validateSQLNamePattern(&buf, access_method_pattern,
+									false, false, NULL, "am.amname", NULL, NULL,
+									&have_where, 1))
+			return false;
 	if (type_pattern)
 	{
 		appendPQExpBuffer(&buf,
@@ -6530,10 +6688,12 @@ listOperatorFamilies(const char *access_method_pattern,
 						  "    WHERE oc.opcfamily = f.oid\n",
 						  have_where ? "AND" : "WHERE");
 		/* Match type name pattern against either internal or external name */
-		processSQLNamePattern(pset.db, &buf, type_pattern, true, false,
-							  "tn.nspname", "t.typname",
-							  "pg_catalog.format_type(t.oid, NULL)",
-							  "pg_catalog.pg_type_is_visible(t.oid)");
+		if (!validateSQLNamePattern(&buf, type_pattern, true, false,
+									"tn.nspname", "t.typname",
+									"pg_catalog.format_type(t.oid, NULL)",
+									"pg_catalog.pg_type_is_visible(t.oid)",
+									NULL, 3))
+			return false;
 		appendPQExpBufferStr(&buf, "  )\n");
 	}
 
@@ -6611,13 +6771,17 @@ listOpFamilyOperators(const char *access_method_pattern,
 							 "  LEFT JOIN pg_catalog.pg_opfamily ofs ON ofs.oid = o.amopsortfamily\n");
 
 	if (access_method_pattern)
-		have_where = processSQLNamePattern(pset.db, &buf, access_method_pattern,
-										   false, false, NULL, "am.amname",
-										   NULL, NULL);
+		if (!validateSQLNamePattern(&buf, access_method_pattern,
+									false, false, NULL, "am.amname",
+									NULL, NULL,
+									&have_where, 1))
+			return false;
 
 	if (family_pattern)
-		processSQLNamePattern(pset.db, &buf, family_pattern, have_where, false,
-							  "nsf.nspname", "of.opfname", NULL, NULL);
+		if (!validateSQLNamePattern(&buf, family_pattern, have_where, false,
+									"nsf.nspname", "of.opfname", NULL, NULL,
+									NULL, 3))
+			return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2,\n"
 						 "  o.amoplefttype = o.amoprighttype DESC,\n"
@@ -6695,12 +6859,16 @@ listOpFamilyFunctions(const char *access_method_pattern,
 						 "  LEFT JOIN pg_catalog.pg_proc p ON ap.amproc = p.oid\n");
 
 	if (access_method_pattern)
-		have_where = processSQLNamePattern(pset.db, &buf, access_method_pattern,
-										   false, false, NULL, "am.amname",
-										   NULL, NULL);
+		if (!validateSQLNamePattern(&buf, access_method_pattern,
+									false, false, NULL, "am.amname",
+									NULL, NULL,
+									&have_where, 1))
+			return false;
 	if (family_pattern)
-		processSQLNamePattern(pset.db, &buf, family_pattern, have_where, false,
-							  "ns.nspname", "of.opfname", NULL, NULL);
+		if (!validateSQLNamePattern(&buf, family_pattern, have_where, false,
+									"ns.nspname", "of.opfname", NULL, NULL,
+									NULL, 3))
+			return false;
 
 	appendPQExpBufferStr(&buf, "ORDER BY 1, 2,\n"
 						 "  ap.amproclefttype = ap.amprocrighttype DESC,\n"
diff --git a/src/fe_utils/string_utils.c b/src/fe_utils/string_utils.c
index bca50ec6de..2cd0134e92 100644
--- a/src/fe_utils/string_utils.c
+++ b/src/fe_utils/string_utils.c
@@ -882,6 +882,9 @@ appendReloptionsArray(PQExpBuffer buffer, const char *reloptions,
  * altnamevar: NULL, or name of an alternative variable to match against name.
  * visibilityrule: clause to use if we want to restrict to visible objects
  * (for example, "pg_catalog.pg_table_is_visible(p.oid)").  Can be NULL.
+ * dbnamebuf: output parameter receiving the database name portion of the
+ * pattern, if any.  Can be NULL.
+ * dotcnt: how many separators were parsed from the pattern, by reference.
  *
  * Formatting note: the text already present in buf should end with a newline.
  * The appended text, if any, will end with one too.
@@ -890,7 +893,8 @@ bool
 processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
 					  bool have_where, bool force_escape,
 					  const char *schemavar, const char *namevar,
-					  const char *altnamevar, const char *visibilityrule)
+					  const char *altnamevar, const char *visibilityrule,
+					  PQExpBuffer dbnamebuf, int *dotcnt)
 {
 	PQExpBufferData schemabuf;
 	PQExpBufferData namebuf;
@@ -900,6 +904,8 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
 	(appendPQExpBufferStr(buf, have_where ? "  AND " : "WHERE "), \
 	 have_where = true, added_clause = true)
 
+	Assert(dotcnt != NULL);
+	*dotcnt = 0;
 	if (pattern == NULL)
 	{
 		/* Default: select all visible objects */
@@ -919,8 +925,8 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
 	 * execute.  Quoting/escaping into SQL literal format will be done below
 	 * using appendStringLiteralConn().
 	 */
-	patternToSQLRegex(PQclientEncoding(conn), NULL, &schemabuf, &namebuf,
-					  pattern, force_escape);
+	patternToSQLRegex(PQclientEncoding(conn), dbnamebuf, &schemabuf, &namebuf,
+					  pattern, force_escape, true, dotcnt);
 
 	/*
 	 * Now decide what we need to emit.  We may run under a hostile
@@ -933,7 +939,7 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
 	 * is >= v12 then we need to force it through explicit COLLATE clauses,
 	 * otherwise the "C" collation attached to "name" catalog columns wins.
 	 */
-	if (namebuf.len > 2)
+	if (namevar && namebuf.len > 2)
 	{
 		/* We have a name pattern, so constrain the namevar(s) */
 
@@ -967,7 +973,7 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
 		}
 	}
 
-	if (schemabuf.len > 2)
+	if (schemavar && schemabuf.len > 2)
 	{
 		/* We have a schema pattern, so constrain the schemavar */
 
@@ -1008,8 +1014,7 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
  * If the dbnamebuf and schemabuf arguments are non-NULL, and the pattern
  * contains two or more dbname/schema/name separators, we parse the portions of
  * the pattern prior to the first and second separators into dbnamebuf and
- * schemabuf, and the rest into namebuf.  (Additional dots in the name portion
- * are not treated as special.)
+ * schemabuf, and the rest into namebuf.
  *
  * If dbnamebuf is NULL and schemabuf is non-NULL, and the pattern contains at
  * least one separator, we parse the first portion into schemabuf and the rest
@@ -1017,24 +1022,49 @@ processSQLNamePattern(PGconn *conn, PQExpBuffer buf, const char *pattern,
  *
  * Otherwise, we parse all the pattern into namebuf.
  *
+ * If the pattern contains more dotted parts than buffers to parse into, the
+ * extra dots will be treated as literal characters and written into the
+ * namebuf, though they will be counted.  Callers should always check the value
+ * returned by reference in dotcnt and handle this error case appropriately.
+ *
  * We surround the regexps with "^(...)$" to force them to match whole strings,
  * as per SQL practice.  We have to have parens in case strings contain "|",
  * else the "^" and "$" will be bound into the first and last alternatives
- * which is not what we want.
+ * which is not what we want.  Whether this is done for dbnamebuf is controlled
+ * by the want_literal_dbname parameter.
  *
  * The regexps we parse into the buffers are appended to the data (if any)
  * already present.  If we parse fewer fields than the number of buffers we
  * were given, the extra buffers are unaltered.
+ *
+ * encoding: the character encoding for the given pattern
+ * dbnamebuf: output parameter receiving the database name portion of the
+ * pattern, if any.  Can be NULL.
+ * schemabuf: output parameter receiving the schema name portion of the
+ * pattern, if any.  Can be NULL.
+ * namebuf: output parameter receiving the database name portion of the
+ * pattern, if any.  Can be NULL.
+ * pattern: user-specified pattern option, or NULL if none ("*" is implied).
+ * force_escape: always quote regexp special characters, even outside
+ * double quotes (else they are quoted only between double quotes).
+ * want_literal_dbname: if true, regexp special characters within the database
+ * name portion of the pattern will not be escaped, nor will the dbname be
+ * converted into a regular expression.
+ * dotcnt: output parameter receiving the number of separators parsed from the
+ * pattern.
  */
 void
 patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
-				  PQExpBuffer namebuf, const char *pattern, bool force_escape)
+				  PQExpBuffer namebuf, const char *pattern, bool force_escape,
+				  bool want_literal_dbname, int *dotcnt)
 {
 	PQExpBufferData buf[3];
+	PQExpBufferData left_literal;
 	PQExpBuffer curbuf;
 	PQExpBuffer maxbuf;
 	int			i;
 	bool		inquotes;
+	bool		left;
 	const char *cp;
 
 	Assert(pattern != NULL);
@@ -1042,7 +1072,9 @@ patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
 
 	/* callers should never expect "dbname.relname" format */
 	Assert(dbnamebuf == NULL || schemabuf != NULL);
+	Assert(dotcnt != NULL);
 
+	*dotcnt = 0;
 	inquotes = false;
 	cp = pattern;
 
@@ -1054,6 +1086,13 @@ patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
 		maxbuf = &buf[0];
 
 	curbuf = &buf[0];
+	if (want_literal_dbname)
+	{
+		left = true;
+		initPQExpBuffer(&left_literal);
+	}
+	else
+		left = false;
 	initPQExpBuffer(curbuf);
 	appendPQExpBufferStr(curbuf, "^(");
 	while (*cp)
@@ -1066,6 +1105,8 @@ patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
 			{
 				/* emit one quote, stay in inquotes mode */
 				appendPQExpBufferChar(curbuf, '"');
+				if (left)
+					appendPQExpBufferChar(&left_literal, '"');
 				cp++;
 			}
 			else
@@ -1076,32 +1117,40 @@ patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
 		{
 			appendPQExpBufferChar(curbuf,
 								  pg_tolower((unsigned char) ch));
+			if (left)
+				appendPQExpBufferChar(&left_literal,
+									  pg_tolower((unsigned char) ch));
 			cp++;
 		}
 		else if (!inquotes && ch == '*')
 		{
 			appendPQExpBufferStr(curbuf, ".*");
+			if (left)
+				appendPQExpBufferChar(&left_literal, '*');
 			cp++;
 		}
 		else if (!inquotes && ch == '?')
 		{
 			appendPQExpBufferChar(curbuf, '.');
+			if (left)
+				appendPQExpBufferChar(&left_literal, '?');
 			cp++;
 		}
-
-		/*
-		 * When we find a dbname/schema/name separator, we treat it specially
-		 * only if the caller requested more patterns to be parsed than we
-		 * have already parsed from the pattern.  Otherwise, dot characters
-		 * are not special.
-		 */
-		else if (!inquotes && ch == '.' && curbuf < maxbuf)
+		else if (!inquotes && ch == '.')
 		{
-			appendPQExpBufferStr(curbuf, ")$");
-			curbuf++;
-			initPQExpBuffer(curbuf);
-			appendPQExpBufferStr(curbuf, "^(");
-			cp++;
+			left = false;
+			if (dotcnt)
+				(*dotcnt)++;
+			if (curbuf < maxbuf)
+			{
+				appendPQExpBufferStr(curbuf, ")$");
+				curbuf++;
+				initPQExpBuffer(curbuf);
+				appendPQExpBufferStr(curbuf, "^(");
+				cp++;
+			}
+			else
+				appendPQExpBufferChar(curbuf, *cp++);
 		}
 		else if (ch == '$')
 		{
@@ -1113,6 +1162,8 @@ patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
 			 * having it possess its regexp meaning.
 			 */
 			appendPQExpBufferStr(curbuf, "\\$");
+			if (left)
+				appendPQExpBufferChar(&left_literal, '$');
 			cp++;
 		}
 		else
@@ -1137,25 +1188,35 @@ patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf, PQExpBuffer schemabuf,
 				appendPQExpBufferChar(curbuf, '\\');
 			i = PQmblenBounded(cp, encoding);
 			while (i--)
+			{
+				if (left)
+					appendPQExpBufferChar(&left_literal, *cp);
 				appendPQExpBufferChar(curbuf, *cp++);
+			}
 		}
 	}
 	appendPQExpBufferStr(curbuf, ")$");
 
-	appendPQExpBufferStr(namebuf, curbuf->data);
-	termPQExpBuffer(curbuf);
-
-	if (curbuf > buf)
+	if (namebuf)
 	{
+		appendPQExpBufferStr(namebuf, curbuf->data);
+		termPQExpBuffer(curbuf);
 		curbuf--;
+	}
+
+	if (schemabuf && curbuf >= buf)
+	{
 		appendPQExpBufferStr(schemabuf, curbuf->data);
 		termPQExpBuffer(curbuf);
+		curbuf--;
+	}
 
-		if (curbuf > buf)
-		{
-			curbuf--;
+	if (dbnamebuf && curbuf >= buf)
+	{
+		if (want_literal_dbname)
+			appendPQExpBufferStr(dbnamebuf, left_literal.data);
+		else
 			appendPQExpBufferStr(dbnamebuf, curbuf->data);
-			termPQExpBuffer(curbuf);
-		}
+		termPQExpBuffer(curbuf);
 	}
 }
diff --git a/src/include/fe_utils/string_utils.h b/src/include/fe_utils/string_utils.h
index 3c88250e6c..a228fe4520 100644
--- a/src/include/fe_utils/string_utils.h
+++ b/src/include/fe_utils/string_utils.h
@@ -55,10 +55,12 @@ extern bool processSQLNamePattern(PGconn *conn, PQExpBuffer buf,
 								  const char *pattern,
 								  bool have_where, bool force_escape,
 								  const char *schemavar, const char *namevar,
-								  const char *altnamevar, const char *visibilityrule);
+								  const char *altnamevar, const char *visibilityrule,
+								  PQExpBuffer dbnamebuf, int *dotcnt);
 
 extern void patternToSQLRegex(int encoding, PQExpBuffer dbnamebuf,
 							  PQExpBuffer schemabuf, PQExpBuffer namebuf,
-							  const char *pattern, bool force_escape);
+							  const char *pattern, bool force_escape,
+							  bool want_literal_dbname, int *dotcnt);
 
 #endif							/* STRING_UTILS_H */
diff --git a/src/test/regress/expected/psql.out b/src/test/regress/expected/psql.out
index 185c505312..95e21d4ff7 100644
--- a/src/test/regress/expected/psql.out
+++ b/src/test/regress/expected/psql.out
@@ -5532,3 +5532,224 @@ SELECT * FROM bla ORDER BY 1;
 # final ON_ERROR_ROLLBACK: off
 DROP TABLE bla;
 DROP FUNCTION psql_error;
+-- check describing invalid multipart names
+\dA regression.heap
+improper qualified name (too many dotted names): regression.heap
+\dA nonesuch.heap
+improper qualified name (too many dotted names): nonesuch.heap
+\dt host.regression.pg_catalog.pg_class
+improper qualified name (too many dotted names): host.regression.pg_catalog.pg_class
+\dt |.pg_catalog.pg_class
+cross-database references are not implemented: |.pg_catalog.pg_class
+\dt nonesuch.pg_catalog.pg_class
+cross-database references are not implemented: nonesuch.pg_catalog.pg_class
+\da host.regression.pg_catalog.sum
+improper qualified name (too many dotted names): host.regression.pg_catalog.sum
+\da +.pg_catalog.sum
+cross-database references are not implemented: +.pg_catalog.sum
+\da nonesuch.pg_catalog.sum
+cross-database references are not implemented: nonesuch.pg_catalog.sum
+\dAc nonesuch.brin
+improper qualified name (too many dotted names): nonesuch.brin
+\dAc regression.brin
+improper qualified name (too many dotted names): regression.brin
+\dAf nonesuch.brin
+improper qualified name (too many dotted names): nonesuch.brin
+\dAf regression.brin
+improper qualified name (too many dotted names): regression.brin
+\dAo nonesuch.brin
+improper qualified name (too many dotted names): nonesuch.brin
+\dAo regression.brin
+improper qualified name (too many dotted names): regression.brin
+\dAp nonesuch.brin
+improper qualified name (too many dotted names): nonesuch.brin
+\dAp regression.brin
+improper qualified name (too many dotted names): regression.brin
+\db nonesuch.pg_default
+improper qualified name (too many dotted names): nonesuch.pg_default
+\db regression.pg_default
+improper qualified name (too many dotted names): regression.pg_default
+\dc host.regression.public.conversion
+improper qualified name (too many dotted names): host.regression.public.conversion
+\dc (.public.conversion
+cross-database references are not implemented: (.public.conversion
+\dc nonesuch.public.conversion
+cross-database references are not implemented: nonesuch.public.conversion
+\dC host.regression.pg_catalog.int8
+improper qualified name (too many dotted names): host.regression.pg_catalog.int8
+\dC ).pg_catalog.int8
+cross-database references are not implemented: ).pg_catalog.int8
+\dC nonesuch.pg_catalog.int8
+cross-database references are not implemented: nonesuch.pg_catalog.int8
+\dd host.regression.pg_catalog.pg_class
+improper qualified name (too many dotted names): host.regression.pg_catalog.pg_class
+\dd [.pg_catalog.pg_class
+cross-database references are not implemented: [.pg_catalog.pg_class
+\dd nonesuch.pg_catalog.pg_class
+cross-database references are not implemented: nonesuch.pg_catalog.pg_class
+\dD host.regression.public.gtestdomain1
+improper qualified name (too many dotted names): host.regression.public.gtestdomain1
+\dD ].public.gtestdomain1
+cross-database references are not implemented: ].public.gtestdomain1
+\dD nonesuch.public.gtestdomain1
+cross-database references are not implemented: nonesuch.public.gtestdomain1
+\ddp host.regression.pg_catalog.pg_class
+improper qualified name (too many dotted names): host.regression.pg_catalog.pg_class
+\ddp {.pg_catalog.pg_class
+cross-database references are not implemented: {.pg_catalog.pg_class
+\ddp nonesuch.pg_catalog.pg_class
+cross-database references are not implemented: nonesuch.pg_catalog.pg_class
+\dE host.regression.public.ft
+improper qualified name (too many dotted names): host.regression.public.ft
+\dE }.public.ft
+cross-database references are not implemented: }.public.ft
+\dE nonesuch.public.ft
+cross-database references are not implemented: nonesuch.public.ft
+\di host.regression.public.tenk1_hundred
+improper qualified name (too many dotted names): host.regression.public.tenk1_hundred
+\di ..public.tenk1_hundred
+improper qualified name (too many dotted names): ..public.tenk1_hundred
+\di nonesuch.public.tenk1_hundred
+cross-database references are not implemented: nonesuch.public.tenk1_hundred
+\dm host.regression.public.mvtest_bb
+improper qualified name (too many dotted names): host.regression.public.mvtest_bb
+\dm ^.public.mvtest_bb
+cross-database references are not implemented: ^.public.mvtest_bb
+\dm nonesuch.public.mvtest_bb
+cross-database references are not implemented: nonesuch.public.mvtest_bb
+\ds host.regression.public.check_seq
+improper qualified name (too many dotted names): host.regression.public.check_seq
+\ds regression|mydb.public.check_seq
+cross-database references are not implemented: regression|mydb.public.check_seq
+\ds nonesuch.public.check_seq
+cross-database references are not implemented: nonesuch.public.check_seq
+\dt host.regression.public.b_star
+improper qualified name (too many dotted names): host.regression.public.b_star
+\dt regres+ion.public.b_star
+cross-database references are not implemented: regres+ion.public.b_star
+\dt nonesuch.public.b_star
+cross-database references are not implemented: nonesuch.public.b_star
+\dv host.regression.public.shoe
+improper qualified name (too many dotted names): host.regression.public.shoe
+\dv regress(ion).public.shoe
+cross-database references are not implemented: regress(ion).public.shoe
+\dv nonesuch.public.shoe
+cross-database references are not implemented: nonesuch.public.shoe
+\des nonesuch.server
+improper qualified name (too many dotted names): nonesuch.server
+\des regression.server
+improper qualified name (too many dotted names): regression.server
+\des nonesuch.server
+improper qualified name (too many dotted names): nonesuch.server
+\des regression.server
+improper qualified name (too many dotted names): regression.server
+\des nonesuch.username
+improper qualified name (too many dotted names): nonesuch.username
+\des regression.username
+improper qualified name (too many dotted names): regression.username
+\dew nonesuch.fdw
+improper qualified name (too many dotted names): nonesuch.fdw
+\dew regression.fdw
+improper qualified name (too many dotted names): regression.fdw
+\df host.regression.public.namelen
+improper qualified name (too many dotted names): host.regression.public.namelen
+\df regres[qrstuv]ion.public.namelen
+cross-database references are not implemented: regres[qrstuv]ion.public.namelen
+\df nonesuch.public.namelen
+cross-database references are not implemented: nonesuch.public.namelen
+\dF host.regression.pg_catalog.arabic
+improper qualified name (too many dotted names): host.regression.pg_catalog.arabic
+\dF regres{1,2}ion.pg_catalog.arabic
+cross-database references are not implemented: regres{1,2}ion.pg_catalog.arabic
+\dF nonesuch.pg_catalog.arabic
+cross-database references are not implemented: nonesuch.pg_catalog.arabic
+\dFd host.regression.pg_catalog.arabic_stem
+improper qualified name (too many dotted names): host.regression.pg_catalog.arabic_stem
+\dFd regres?ion.pg_catalog.arabic_stem
+cross-database references are not implemented: regres?ion.pg_catalog.arabic_stem
+\dFd nonesuch.pg_catalog.arabic_stem
+cross-database references are not implemented: nonesuch.pg_catalog.arabic_stem
+\dFp host.regression.pg_catalog.default
+improper qualified name (too many dotted names): host.regression.pg_catalog.default
+\dFp ^regression.pg_catalog.default
+cross-database references are not implemented: ^regression.pg_catalog.default
+\dFp nonesuch.pg_catalog.default
+cross-database references are not implemented: nonesuch.pg_catalog.default
+\dFt host.regression.pg_catalog.ispell
+improper qualified name (too many dotted names): host.regression.pg_catalog.ispell
+\dFt regression$.pg_catalog.ispell
+cross-database references are not implemented: regression$.pg_catalog.ispell
+\dFt nonesuch.pg_catalog.ispell
+cross-database references are not implemented: nonesuch.pg_catalog.ispell
+\dg nonesuch.pg_database_owner
+improper qualified name (too many dotted names): nonesuch.pg_database_owner
+\dg regression.pg_database_owner
+improper qualified name (too many dotted names): regression.pg_database_owner
+\dL host.regression.plpgsql
+improper qualified name (too many dotted names): host.regression.plpgsql
+\dL *.plpgsql
+cross-database references are not implemented: *.plpgsql
+\dL nonesuch.plpgsql
+cross-database references are not implemented: nonesuch.plpgsql
+\dn host.regression.public
+improper qualified name (too many dotted names): host.regression.public
+\dn """".public
+cross-database references are not implemented: """".public
+\dn nonesuch.public
+cross-database references are not implemented: nonesuch.public
+\do host.regression.public.!=-
+improper qualified name (too many dotted names): host.regression.public.!=-
+\do "regression|mydb".public.!=-
+cross-database references are not implemented: "regression|mydb".public.!=-
+\do nonesuch.public.!=-
+cross-database references are not implemented: nonesuch.public.!=-
+\dO host.regression.pg_catalog.POSIX
+improper qualified name (too many dotted names): host.regression.pg_catalog.POSIX
+\dO .pg_catalog.POSIX
+cross-database references are not implemented: .pg_catalog.POSIX
+\dO nonesuch.pg_catalog.POSIX
+cross-database references are not implemented: nonesuch.pg_catalog.POSIX
+\dp host.regression.public.a_star
+improper qualified name (too many dotted names): host.regression.public.a_star
+\dp "regres+ion".public.a_star
+cross-database references are not implemented: "regres+ion".public.a_star
+\dp nonesuch.public.a_star
+cross-database references are not implemented: nonesuch.public.a_star
+\dP host.regression.public.mlparted
+improper qualified name (too many dotted names): host.regression.public.mlparted
+\dP "regres(sion)".public.mlparted
+cross-database references are not implemented: "regres(sion)".public.mlparted
+\dP nonesuch.public.mlparted
+cross-database references are not implemented: nonesuch.public.mlparted
+\drds nonesuch.lc_messages
+improper qualified name (too many dotted names): nonesuch.lc_messages
+\drds regression.lc_messages
+improper qualified name (too many dotted names): regression.lc_messages
+\dRp public.mypub
+improper qualified name (too many dotted names): public.mypub
+\dRp regression.mypub
+improper qualified name (too many dotted names): regression.mypub
+\dRs public.mysub
+improper qualified name (too many dotted names): public.mysub
+\dRs regression.mysub
+improper qualified name (too many dotted names): regression.mysub
+\dT host.regression.public.widget
+improper qualified name (too many dotted names): host.regression.public.widget
+\dT "regression{1,2}".public.widget
+cross-database references are not implemented: "regression{1,2}".public.widget
+\dT nonesuch.public.widget
+cross-database references are not implemented: nonesuch.public.widget
+\dx regression.plpgsql
+improper qualified name (too many dotted names): regression.plpgsql
+\dx nonesuch.plpgsql
+improper qualified name (too many dotted names): nonesuch.plpgsql
+\dX host.regression.public.func_deps_stat
+improper qualified name (too many dotted names): host.regression.public.func_deps_stat
+\dX "^regression$".public.func_deps_stat
+cross-database references are not implemented: "^regression$".public.func_deps_stat
+\dX nonesuch.public.func_deps_stat
+cross-database references are not implemented: nonesuch.public.func_deps_stat
+\dy regression.myevt
+improper qualified name (too many dotted names): regression.myevt
+\dy nonesuch.myevt
+improper qualified name (too many dotted names): nonesuch.myevt
diff --git a/src/test/regress/sql/psql.sql b/src/test/regress/sql/psql.sql
index 8f49a5f347..27a3c3a26a 100644
--- a/src/test/regress/sql/psql.sql
+++ b/src/test/regress/sql/psql.sql
@@ -1457,3 +1457,115 @@ SELECT * FROM bla ORDER BY 1;
 \echo '# final ON_ERROR_ROLLBACK:' :ON_ERROR_ROLLBACK
 DROP TABLE bla;
 DROP FUNCTION psql_error;
+
+-- check describing invalid multipart names
+\dA regression.heap
+\dA nonesuch.heap
+\dt host.regression.pg_catalog.pg_class
+\dt |.pg_catalog.pg_class
+\dt nonesuch.pg_catalog.pg_class
+\da host.regression.pg_catalog.sum
+\da +.pg_catalog.sum
+\da nonesuch.pg_catalog.sum
+\dAc nonesuch.brin
+\dAc regression.brin
+\dAf nonesuch.brin
+\dAf regression.brin
+\dAo nonesuch.brin
+\dAo regression.brin
+\dAp nonesuch.brin
+\dAp regression.brin
+\db nonesuch.pg_default
+\db regression.pg_default
+\dc host.regression.public.conversion
+\dc (.public.conversion
+\dc nonesuch.public.conversion
+\dC host.regression.pg_catalog.int8
+\dC ).pg_catalog.int8
+\dC nonesuch.pg_catalog.int8
+\dd host.regression.pg_catalog.pg_class
+\dd [.pg_catalog.pg_class
+\dd nonesuch.pg_catalog.pg_class
+\dD host.regression.public.gtestdomain1
+\dD ].public.gtestdomain1
+\dD nonesuch.public.gtestdomain1
+\ddp host.regression.pg_catalog.pg_class
+\ddp {.pg_catalog.pg_class
+\ddp nonesuch.pg_catalog.pg_class
+\dE host.regression.public.ft
+\dE }.public.ft
+\dE nonesuch.public.ft
+\di host.regression.public.tenk1_hundred
+\di ..public.tenk1_hundred
+\di nonesuch.public.tenk1_hundred
+\dm host.regression.public.mvtest_bb
+\dm ^.public.mvtest_bb
+\dm nonesuch.public.mvtest_bb
+\ds host.regression.public.check_seq
+\ds regression|mydb.public.check_seq
+\ds nonesuch.public.check_seq
+\dt host.regression.public.b_star
+\dt regres+ion.public.b_star
+\dt nonesuch.public.b_star
+\dv host.regression.public.shoe
+\dv regress(ion).public.shoe
+\dv nonesuch.public.shoe
+\des nonesuch.server
+\des regression.server
+\des nonesuch.server
+\des regression.server
+\des nonesuch.username
+\des regression.username
+\dew nonesuch.fdw
+\dew regression.fdw
+\df host.regression.public.namelen
+\df regres[qrstuv]ion.public.namelen
+\df nonesuch.public.namelen
+\dF host.regression.pg_catalog.arabic
+\dF regres{1,2}ion.pg_catalog.arabic
+\dF nonesuch.pg_catalog.arabic
+\dFd host.regression.pg_catalog.arabic_stem
+\dFd regres?ion.pg_catalog.arabic_stem
+\dFd nonesuch.pg_catalog.arabic_stem
+\dFp host.regression.pg_catalog.default
+\dFp ^regression.pg_catalog.default
+\dFp nonesuch.pg_catalog.default
+\dFt host.regression.pg_catalog.ispell
+\dFt regression$.pg_catalog.ispell
+\dFt nonesuch.pg_catalog.ispell
+\dg nonesuch.pg_database_owner
+\dg regression.pg_database_owner
+\dL host.regression.plpgsql
+\dL *.plpgsql
+\dL nonesuch.plpgsql
+\dn host.regression.public
+\dn """".public
+\dn nonesuch.public
+\do host.regression.public.!=-
+\do "regression|mydb".public.!=-
+\do nonesuch.public.!=-
+\dO host.regression.pg_catalog.POSIX
+\dO .pg_catalog.POSIX
+\dO nonesuch.pg_catalog.POSIX
+\dp host.regression.public.a_star
+\dp "regres+ion".public.a_star
+\dp nonesuch.public.a_star
+\dP host.regression.public.mlparted
+\dP "regres(sion)".public.mlparted
+\dP nonesuch.public.mlparted
+\drds nonesuch.lc_messages
+\drds regression.lc_messages
+\dRp public.mypub
+\dRp regression.mypub
+\dRs public.mysub
+\dRs regression.mysub
+\dT host.regression.public.widget
+\dT "regression{1,2}".public.widget
+\dT nonesuch.public.widget
+\dx regression.plpgsql
+\dx nonesuch.plpgsql
+\dX host.regression.public.func_deps_stat
+\dX "^regression$".public.func_deps_stat
+\dX nonesuch.public.func_deps_stat
+\dy regression.myevt
+\dy nonesuch.myevt
-- 
2.35.1

