如何用SQL排除重復結果只取字段最大值的記錄?
要求得到的結果(即是PID相同的記錄只取ID值最大的那一條)。
復制代碼 代碼如下:
select * from [Sheet1$] a
where ID not exists (select 1 from [Sheet1$] where PID=a.PID and ID>a.ID)
select a.* from [Sheet1$] a inner join (select PID,max(ID) as max_id from [Sheet1$] group by PID) b on a.PID=b.PID and a.ID=b.max_id