Mysql 什么'；这个语法怎么了？

我使用的是MYSQL 5.7

您不能在

where

子句中使用聚合函数。您需要一个

具有

子句：

select count(*),snum from enrolled group by snum where count(*)=(select count(distinct(cname)) from enrolled;);

select count(*), snum
from enrolled
group by snum 
having count(*) = (select count(distinct cname ) from enrolled);

---

此外，查询结束时只能显示一个分号。而且，尽管这不是语法错误，

distinct

不是函数，所以它不需要括号

不能在

where

子句中使用聚合函数。您需要一个

具有

子句：

select count(*),snum from enrolled group by snum where count(*)=(select count(distinct(cname)) from enrolled;);

select count(*), snum
from enrolled
group by snum 
having count(*) = (select count(distinct cname ) from enrolled);

---

此外，查询结束时只能显示一个分号。而且，尽管这不是语法错误，

distinct

不是函数，所以它不需要括号

不能在

where

子句中使用聚合术语。相反，您应该使用

having

子句：

select count(*),snum from enrolled group by snum where count(*)=(select count(distinct(cname)) from enrolled;);

select count(*), snum
from enrolled
group by snum 
having count(*) = (select count(distinct cname ) from enrolled);

---

不能在

where

子句中使用聚合术语。相反，您应该使用

having

子句：

select count(*),snum from enrolled group by snum where count(*)=(select count(distinct(cname)) from enrolled;);

select count(*), snum
from enrolled
group by snum 
having count(*) = (select count(distinct cname ) from enrolled);