sql – 编写自联接查询?
发布时间:2020-05-24 13:43:29 所属栏目:MsSql 来源:互联网
导读:我有下表的值 CREATE TABLE #tmpEmployee(ID int, EmpName varchar(50), EmpBossID int)insert into #tmpEmployee values ( 1, Abhijit, 2);insert into #tmpEmployee values ( 2, Haris, 3);insert into #tmpEmpl
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我有下表的值 CREATE TABLE #tmpEmployee(ID int,EmpName varchar(50),EmpBossID int) insert into #tmpEmployee values ( 1,'Abhijit',2); insert into #tmpEmployee values ( 2,'Haris',3); insert into #tmpEmployee values ( 3,'Sanal',0); 现在我希望结果如下 ID EmpName BossName 1 Abhijit Haris 2 Haris Sanal 所以我写了以下查询. select E1.ID,E1.EmpName,E.EmpName as BossName from #tmpEmployee E inner join #tmpEmployee E1 on E1.EmpBossID=E.ID. 但问题是第3名员工(Sanal)没有老板. ID EmpName BossName 1 Abhijit Haris 2 Haris Sanal 3 Sanal Null 我该怎么办? 解决方法使用正确加入select E1.ID,E.EmpName as BossName from #tmpEmployee E right join #tmpEmployee E1 on E1.EmpBossID=E.ID ID EmpName BossName 1 Abhijit Haris 2 Haris Sanal 3 Sanal NULL 我觉得对你好 (编辑:安卓应用网) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |
