聚合函数的SQL比较

Question

在ACCESS 2007中运行以下SQL时

  

选择位置，   COUNT（ApartmentBuildings）AS   TotalBuildingsManaged From Apartments   COUNT（ApartmentBuildings）＆gt; 3   按地点分组按顺序排列   COUNT（ApartmentBuildings）DESC;

我收到以下错误：

在where子句中不能有聚合函数。如何构建此查询以获取所有具有大于3的ApartmentBuildings数量的位置？

Answer 1

使用having代替where：

Select Location, COUNT(ApartmentBuildings) AS TotalIBuildingsManaged 
From Apartments 
Group By Location
Having COUNT(ApartmentBuildings) > 3  
Order By COUNT(ApartmentBuildings) DESC;

了解更多信息see this page

Answer 2

您需要使用HAVING子句

Select Location, COUNT(ApartmentBuildings) AS TotalIBuildingsManaged 
From Apartments 
Group By Location 
HAVING COUNT(ApartmentBuildings) > 3