Mysql变量无法通过php mysql查询工作

Question

我有这个问题:

$query = " 

 SET @points := -1;
 SET @num := 0;

 SELECT `id`,`rank`,
 @num := if(@points = `rank`, @num, @num + 1) as `point_rank`
 FROM `said`
 ORDER BY `rank` *1 desc, `id` asc";

我正在使用来自php的这个查询; 给我这个错误:

您的SQL语法有错误; 检查与MySQL服务器版本对应的手册,以便在'SET @num:= 0附近使用正确的语法;

如果我在phpmyadmin Sql查询面板中复制并粘贴该代码,它可以正常工作,但是从PHP代码行开始它不起作用,看起来设置Vars时会出现问题.

Answer 1

SET您是否尝试使用以下命令而不是单独设置变量CROSS JOIN？

$query = " 

SELECT `id`,
  `rank`,
  @num := if(@points = `rank`, @num, @num + 1) as `point_rank`
FROM `said`
CROSS JOIN (SELECT @points:=-1, @num:=0) c
ORDER BY `rank` *1 desc, `id` asc";