根據

[轉][MySQL] 如何用 SELECT 查詢 產生一個自動遞增的序號欄位

和

[轉][MYSQL]將查詢結果更新至資料表 UPDATE for SELECT

的範例來綜合寫出

1. UPDATE
2. pay AS A,
3. (SELECT @s:=@s+1 as seq, id FROM pay, (SELECT @s:= 0) AS s ORDER BY  `pay`.`id` asc ) AS B
4. SET A.`seq`=B.`seq`
5. WHERE A.id=B.id