如何使用mysql将查询结果存储在variables中

SET @v1 := SELECT COUNT(*) FROM user_rating; SELECT @v1 

当我用setvariables执行这个查询时，显示这个错误。

 Error Code : 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'SELECT count(*) FROM user_rating' at line 1 Execution Time : 00:00:00:000 Transfer Time : 00:00:00:000 Total Time : 00:00:00:000 (1 row(s) returned) Execution Time : 00:00:00:343 Transfer Time : 00:00:00:000 Total Time : 00:00:00:343 

Answer 1

用圆括号select的环绕声。

 SET @v1 := (SELECT COUNT(*) FROM user_rating); SELECT @v1; 

Answer 2

此外，如果您想通过一个查询一次设置多个variables，则可以使用其他语法来设置variables，如下所示： SELECT @varname:=value 。

一个实际的例子：

 SELECT @total_count:=COUNT(*), @total_price:=SUM(quantity*price) FROM items ... 

Answer 3

用这个

  SELECT weight INTO @x FROM p_status where tcount=['value'] LIMIT 1; 

testing和工作很好…