前言原本這個主題應該與DQL 查詢資料（SELECT） 放在一起，後來想想這兩個子句還是特別獨立出來，因為相較於其他子句，其他子句是非常簡單易懂的， ... ... <看更多>

You can use having without using group by but on aggregate function. select avg(price) from tbltemp having avg(price) >= 2. In the MSDN link you provided, ... ... <看更多>

No. They don't have to coexist, as proved by the fact that the following query in Oracle works: select * from dual having 1 = 1;. ... <看更多>