查出来的列表添加序号

SELECT            @rownum := @rownum + 1 AS serialNum,obj.*        FROM            (                SELECT                    z.id AS "id",                    z. NAME AS "name",                    ifnull(e.score, 0) AS "score",                    z.photo AS "photo"                FROM                    z_user z                LEFT JOIN exchange.e_score e ON e.user_id = z.id            where                    z.Status = 1                                ORDER BY                    e.score DESC            ) AS obj,            (SELECT @rownum := 0) r