在數據庫中某表中,存在着些相同的記錄,如何能用SQL語句,刪除掉重復的呢1、查找表中多余的重復記錄,重復記錄是根據單個字段(peopleId)來判斷select * from peoplewhere peopleId in (select peopleId from people group ...
方法一: select from tablename where id in select id from tablename group by id having count id gt 方法二: select DISTINCT t. from select from Goods g t ...
2017-12-25 16:50 0 955 推薦指數:
在數據庫中某表中,存在着些相同的記錄,如何能用SQL語句,刪除掉重復的呢1、查找表中多余的重復記錄,重復記錄是根據單個字段(peopleId)來判斷select * from peoplewhere peopleId in (select peopleId from people group ...
select user_id from dt_orders where datatype=10 and status=3 group by user_id having count(*)>1 ...
返回operation表中time列的唯一值 語句1 select time from operation group by time having count(time) > 1 語句2 select distinct time from operation; ...
select * from (SELECT titleid,count(titleid) c FROM [DragonGuoShi].[dbo].[ArticleInfo] group by tit ...
...
1.查詢單列重復: 2.查詢多列重復 ...
1.查詢單列重復(table:表名,name 字段名): select * from table where name in (select name from table group by name having count(name) > 1) 2.查詢多列重復(table:表名 ...
去掉重復數據的方法: 第一種:distinct 根據單個字段去重,能精確去重; 作用在多個字段時,只有當這幾個字段的完全相同時,才能去重; 關鍵字distinct只能放在SQL語句中的第一個,才會起作用 上圖舉例說明:圖中student_name 為 test ...