Fixed #27323 -- Optimized Oracle introspection by using USER_SEQUENCES instead of USER_CATALOG.

django/db/backends/oracle/operations.py

@@ -54,8 +54,8 @@ END;
 DECLARE
     i INTEGER;
 BEGIN
-    SELECT COUNT(*) INTO i FROM USER_CATALOG
-        WHERE TABLE_NAME = '%(sq_name)s' AND TABLE_TYPE = 'SEQUENCE';
+    SELECT COUNT(1) INTO i FROM USER_SEQUENCES
+        WHERE SEQUENCE_NAME = '%(sq_name)s';
     IF i = 0 THEN
         EXECUTE IMMEDIATE 'CREATE SEQUENCE "%(sq_name)s"';
     END IF;

django/db/backends/oracle/schema.py

@@ -40,8 +40,8 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
             DECLARE
                 i INTEGER;
             BEGIN
-                SELECT COUNT(*) INTO i FROM USER_CATALOG
-                    WHERE TABLE_NAME = '%(sq_name)s' AND TABLE_TYPE = 'SEQUENCE';
+                SELECT COUNT(1) INTO i FROM USER_SEQUENCES
+                    WHERE SEQUENCE_NAME = '%(sq_name)s';
                 IF i = 1 THEN
                     EXECUTE IMMEDIATE 'DROP SEQUENCE "%(sq_name)s"';
                 END IF;