db.user_role.dropIndex("uid_1");
db.user_role.dropIndex("role_id_1");
db.user_role.dropIndex("brand_1");
db.user_role.dropIndex("status_1");
db.user_role.dropIndex("brand_1_role_id_1");
db.user_role.dropIndex("brand_1_status_1");
db.user_role.dropIndex("create_time_1");