我可以在哪里放置SELECT @rank：= 0在此查询中

Question

我需要将set @rank:=0;置于此查询中，但我可以在哪里放置它？

SELECT @rank:=@rank+1 AS rank, p.* FROM points p 
inner join distributor d 
on p.distributor_id=d.id_distributor 
where p.month='$prev_month' 
and d.group='$dist_group' 
ORDER BY p.tot_point DESC 

我有主查询之前，使用mysql_query("set @rank:=0;");，它的作品。但在另一台服务器中不起作用。

有什么想法？

Answer 1

SELECT @rank:=@rank+1 AS rank, p.* FROM points p, (SELECT @rank:=0) AS dummy 
inner join distributor d 
on p.distributor_id=d.id_distributor 
where p.month='$prev_month' 
and d.group='$dist_group' 
ORDER BY p.tot_point DESC 

基本上只是在FROM points p之后加, (SELECT @rank:=0) AS dummy。

我对这个查询首选布局：

SELECT @rank := @rank + 1 AS rank, p.* 
FROM 
    points AS p 
    CROSS JOIN 
    (SELECT @rank:=0) AS dummy 
    INNER JOIN 
    distributor AS d 
     ON p.distributor_id = d.id_distributor 
WHERE p.month = '$prev_month' 
    AND d.group='$dist_group' 
ORDER BY p.tot_point DESC ;