MYSQL：根据一张表的查询结果更新另一张表（将某字段内容设定为序号）

 

 

# SELECT row_num(),* FROM TABLE_NAME;
SET @i=0;
update TABLE_NAME h, (SELECT COL_A,COL_B,@i:=@i+1 AS 'need'
FROM TABLE_NAME ) n set h.id = n.need where h.COL_A = n.COL_A and h.COL_B = n.COL_B