SET @v1 := SELECT COUNT(*) FROM user_rating;
SELECT @v1
When I execute this query with set
variable this error is shown.
当我使用set变量执行此查询时,将显示此错误。
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
3 个解决方案
#1
101
Surround that select with parentheses.
用圆括号括住选择。
SET @v1 := (SELECT COUNT(*) FROM user_rating);
SELECT @v1;
#2
22
Additionally, if you want to set multiple variables at once by one query, you can use the other syntax for setting variables which goes like this: SELECT @varname:=value
.
另外,如果您想一次通过一个查询设置多个变量,您可以使用其他语法来设置像这样的变量:选择@varname:=值。
A practical example:
一个实际的例子:
SELECT @total_count:=COUNT(*), @total_price:=SUM(quantity*price) FROM items ...
#3
8
use this
使用这个
SELECT weight INTO @x FROM p_status where tcount=['value'] LIMIT 1;
tested and workes fine...
测试和附件细……
#1
101
Surround that select with parentheses.
用圆括号括住选择。
SET @v1 := (SELECT COUNT(*) FROM user_rating);
SELECT @v1;
#2
22
Additionally, if you want to set multiple variables at once by one query, you can use the other syntax for setting variables which goes like this: SELECT @varname:=value
.
另外,如果您想一次通过一个查询设置多个变量,您可以使用其他语法来设置像这样的变量:选择@varname:=值。
A practical example:
一个实际的例子:
SELECT @total_count:=COUNT(*), @total_price:=SUM(quantity*price) FROM items ...
#3
8
use this
使用这个
SELECT weight INTO @x FROM p_status where tcount=['value'] LIMIT 1;
tested and workes fine...
测试和附件细……