--- /dev/null
+define mw_prefix='{$wgDBprefix}';
+
+ALTER TABLE &mw_prefix.user_groups ADD (
+ug_expiry TIMESTAMP(6) WITH TIME ZONE NULL
+);
+DROP INDEX IF EXISTS &mw_prefix.user_groups_u01;
+ALTER TABLE &mw_prefix.user_groups ADD CONSTRAINT &mw_prefix.user_groups_pk PRIMARY KEY (ug_user,ug_group);
+CREATE INDEX &mw_prefix.user_groups_i02 ON &mw_prefix.user_groups (ug_expiry);