--- /dev/null
+ CREATE TABLE /*_*/user_former_groups_tmp (
+ ufg_user int unsigned NOT NULL default 0,
+ ufg_group varbinary(255) NOT NULL default ''
+) /*$wgDBTableOptions*/;
+
+INSERT INTO /*_*/user_former_groups_tmp
+ SELECT ufg_user, ufg_group
+ FROM /*_*/user_former_groups;
+
+DROP TABLE /*_*/user_former_groups;
+
+ALTER TABLE /*_*/user_former_groups_tmp RENAME TO /*_*/user_former_groups;
+
+CREATE UNIQUE INDEX /*i*/ufg_user_group ON /*_*/user_former_groups (ufg_user,ufg_group);
+