Merge pull request #135926 from cockroachdb/blathers/backport-release…

…-24.1-135910

release-24.1: sql/schemachanger: handle empty schemas gracefully

pkg/sql/logictest/testdata/logic_test/schema

@@ -1379,6 +1379,17 @@ RESET CLUSTER SETTING sql.auth.public_schema_create_privilege.enabled
 
 subtest end
 
+
+subtest schema_with_temp_in_name
+
+statement ok
+CREATE SCHEMA my_pg_temp_123_123;
+
+statement ok
+DROP SCHEMA  my_pg_temp_123_123;
+
+subtest end
+
 # Regression test for #126244: during Memo staleness checking, check object
 # resolution before privileges, to avoid spurious privilege errors.
 subtest check_privileges_after_resolution
@@ -1470,3 +1481,25 @@ SELECT qux();
 NULL
 
 subtest end
+
+subtest empty_schema_name
+
+user root
+
+statement ok
+set role root;
+use defaultdb;
+
+skipif config local-legacy-schema-changer
+skipif config local-mixed-23.1
+statement error pgcode 42601 pq: empty schema name
+CREATE SCHEMA ""."";
+
+onlyif config local-legacy-schema-changer
+statement error pgcode 3D000 pq: database \"\" does not exist
+CREATE SCHEMA ""."";
+
+statement error pgcode 42601 pq: .*empty schema name
+CREATE SCHEMA "";
+
+subtest end

pkg/sql/schemachanger/scbuild/builder_state.go

@@ -1790,8 +1790,7 @@ func (b *builderState) serializeUserDefinedTypes(
 
 func (b *builderState) ResolveDatabasePrefix(schemaPrefix *tree.ObjectNamePrefix) {
 	if schemaPrefix.SchemaName == "" || !schemaPrefix.ExplicitSchema {
-		panic(errors.AssertionFailedf("schema name empty when resolving database prefix for a " +
-			"schema name"))
+		panic(pgerror.Newf(pgcode.Syntax, "empty schema name"))
 	}
 	if schemaPrefix.CatalogName == "" {
 		schemaPrefix.CatalogName = tree.Name(b.cr.CurrentDatabase())