Improve the check for pg_catalog.line data type in pg_upgrade

tvondra · tvondra · commit 235a52ca0f26 · 2019-10-16T13:31:00.000+02:00
The pg_upgrade check for pg_catalog.line data type when upgrading from 9.3 had a couple of issues with domains and composite types. Firstly, it triggered false positives for composite types unused in objects with storage. This was enough to trigger an unnecessary pg_upgrade failure: CREATE TYPE line_composite AS (l pg_catalog.line) On the other hand, this only happened with composite types directly on the pg_catalog.line data type, but not with a domain. So this was not detected CREATE DOMAIN line_domain AS pg_catalog.line; CREATE TYPE line_composite_2 AS (l line_domain); unlike the first example. These false positives and inconsistencies are unfortunate, but what's worse we've failed to detected objects using the pg_catalog.line data type through a domain. So we missed cases like this CREATE TABLE t (l line_composite_2); The consequence is clusters broken after a pg_upgrade. This fixes these false positives and false negatives by using the same recursive CTE introduced by eaf900e for sql_identifier. 9.3 did not support domains on composite types, but we can still have multi-level composite types. Backpatch all the way to 9.4, where the format for pg_catalog.line data type changed. Author: Tomas Vondra Backpatch-to: 9.4- Discussion: https://postgr.es/m/16045-673e8fa6b5ace196%40postgresql.org
diff --git a/contrib/pg_upgrade/version.c b/contrib/pg_upgrade/version.c
@@ -127,14 +127,42 @@ old_9_3_check_for_line_data_type_usage(ClusterInfo *cluster)
 		DbInfo	   *active_db = &cluster->dbarr.dbs[dbnum];
 		PGconn	   *conn = connectToServer(cluster, active_db->db_name);
 
+		/*
+		 * The pg_catalog.line type may be wrapped in a domain or composite
+		 * type, or both (9.3 did not allow domains on composite types, but
+		 * there may be multi-level composite type). To detect these cases
+		 * we need a recursive CTE.
+		 */
 		res = executeQueryOrDie(conn,
+								"WITH RECURSIVE oids AS ( "
+		/* the pg_catalog.line type itself */
+								"	SELECT 'pg_catalog.line'::pg_catalog.regtype AS oid "
+								"	UNION ALL "
+								"	SELECT * FROM ( "
+		/* domains on the type */
+								"		WITH x AS (SELECT oid FROM oids) "
+								"			SELECT t.oid FROM pg_catalog.pg_type t, x WHERE typbasetype = x.oid AND typtype = 'd' "
+								"			UNION "
+		/* composite types containing the type */
+								"			SELECT t.oid FROM pg_catalog.pg_type t, pg_catalog.pg_class c, pg_catalog.pg_attribute a, x "
+								"			WHERE t.typtype = 'c' AND "
+								"				  t.oid = c.reltype AND "
+								"				  c.oid = a.attrelid AND "
+								"				  NOT a.attisdropped AND "
+								"				  a.atttypid = x.oid "
+								"	) foo "
+								") "
 								"SELECT n.nspname, c.relname, a.attname "
 								"FROM	pg_catalog.pg_class c, "
 								"		pg_catalog.pg_namespace n, "
 								"		pg_catalog.pg_attribute a "
 								"WHERE	c.oid = a.attrelid AND "
 								"		NOT a.attisdropped AND "
-								"		a.atttypid = 'pg_catalog.line'::pg_catalog.regtype AND "
+								"		a.atttypid IN (SELECT oid FROM oids) AND "
+								"		c.relkind IN ("
+								CppAsString2(RELKIND_RELATION) ", "
+								CppAsString2(RELKIND_MATVIEW) ", "
+								CppAsString2(RELKIND_INDEX) ") AND "
 								"		c.relnamespace = n.oid AND "
 		/* exclude possible orphaned temp tables */
 								"		n.nspname !~ '^pg_temp_' AND "
