带有Join的SQL自查询

Question

我在下面的下一栏中使用自我查询需要经理姓名。有人可以帮忙吗？

eid  ename            ecity    esal  dno  managerid
1001 Amit Kumar       Delhi    20000 101       1005    
1002 Amit Kumar       Delhi    20000 101       1005
1003 Rahul Awasthi    Delhi    20000 101       NULL
1004 Manish Singh     Delhi    30000 101       1003
1005 Neetu Kumari     Jasola   50000 102       NULL    
1006 Jiya Bharti      Jasola   60000 102       1005    
1007 Priya Bharti     Jasola   50000 102       1003    
1008 Sulekha          amritsar 25000 102       1005    
1009 Sunil Kumar      amritsar 39000 103       1003    
1010 Satish           amritsar 45000 103       1003    
1011 Sunaina          amritsar 49000 104       1003    
1012 Arun             kalkaji 100000 104       1005    
1013 Rupa             kalkaji  70000 104       NULL    
1014 Ravi             kalkaji  65000 105       NULL    
1015 Nanch Srivastata delhi    55000 105       NULL    
1016 Rahul            Kalkaji  30000 NULL      NULL    
1017 Sunil            Kalkaji  35000 NULL      NULL

Answer 1

您需要使用self join

select e.*,m.ename as ManagerName
    from yourtable e
    left join yourtable m on e.managerid = m.eid