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amarnathtnl

 Profile Answers by amarnathtnl 

• Jun 29th, 2007

 

hi,
The answer for ur first Ques is

select * from emp where empno IN(select mgr,count(*) from emp group by mgr having count(*)>=1)


TO SEE THE EXISTING CONSTRAINTS ON the TABLE  emp


select * from user_constraints where table_name='EMP';

note : table name must be given in capitals