查询的语法有什么问题？

Question

这是我的查询文本，但有语法错误。

select cc, sum(a.hours),b.labcost
from labour a,othshop b
where lab_cd='hs' and a.mon=03 and a.yr=2010
group by a.cc
HAVING a.cc=b.occ AND b.mon=03 and b.yr=2010;

所有表格都存在。此查询的文本有什么问题？

Answer 1

having不需要，只是：

select a.cc, sum(a.hours),b.labcost
from labour a,othshop b
where lab_cd='hs' and a.mon=03 and a.yr=2010
and a.cc=b.occ AND b.mon=03 and b.yr=2010
group by a.cc, b.labcost

请注意 b.labcost 已添加到 GROUP BY。否则，您需要对其执行聚合，例如 avg(b.labcost)