其中count函数在where子句中的SQL查询

Question

我有桌子跟踪部门和预算中心之间的关联.该协会是多对多的.现在我想只显示那些与其关联的预算中心超过10个的部门.所以我的查询应该是这样的

select dept,
       count(budget_centers) as bcCount
from myTable
where bcCount > 10
group by dept

现在oracle会给出一个错误,说"bcCount"是一个无效的标识符.有没有办法重新定义oracle中可接受的查询

Answer 1

这就是该having条款的用途:

select dept,
       count(budget_centers) as bcCount
from myTable
group by dept
having count(budget_centers) > 10

以下是本手册的相关部分:

• http://docs.oracle.com/cd/E11882_01/server.112/e26088/statements_10002.htm#i2066419
• http://docs.oracle.com/cd/E11882_01/server.112/e26088/statements_10002.htm#SQLRF55384