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  • mysql在查询结果列表前添加一列递增的序号列(最简)

    SELECT @rownum:=@rownum+1 AS 序号, t_user.* FROM  t_user ,(SELECT @rownum:=0) r  -- 最简写法1

    更多写法供参考:

     ①  select (@rowNO := @rowNo+1) AS rowno,uid,uname from (SELECT *  FROM t_user ) ;


     ②  select (@rowNO := @rowNo+1) AS rowno,a.* from (SELECT * FROM t_user) a,(select @rowNO :=0) b ;


     ③  set @rn=0; select @rn:=@rn+1 as rn, m.* from (select * from t_user  )m; -- 连续执行两个语句


     ④  select (@rowNO := @rowNo+1) AS 序号,a.* from  t_user a,(select @rowNO :=0) b  -- 最简写法2 

    注意:@rownum的写法不唯一,但一定有@,等于号写法一定是:=(冒号等于)

    以下写法都可行:

    SELECT @xxoo:=@xxoo+1 AS 序号, t_user.* FROM  t_user ,(SELECT @xxoo:=0) r;  

    SELECT @1:=@1+1 AS 序号, t_user.* FROM  t_user ,(SELECT @1:=0) r;

    SELECT @:=@+1 AS 序号, a.* FROM  t_user a ,(SELECT @:=0) r; (首推)  

    来张查询结果图:

     
    https://blog.csdn.net/superit401/article/details/78056654?locationNum=8&fps=1
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  • 原文地址:https://www.cnblogs.com/gantoday/p/8662347.html
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