What is a self join ?

Answer Posted / ram

Normally we joins for retrieve data from more than 1 table

In some cases we need to join 1 table itself to join itself
condition is table having two column with same data type &
size but name are different
In emp table empno & mgrno are two columns example for this


select ename,job,sal,e.empno,m.mgrno from emp e inner join
emp m on m.mgrno=e.empno

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