Answer / abhijit

The start with .. connect by clause can be used to select
data that has a hierarchical relationship (usually some sort
of parent->child (boss->employee or thing->parts).


select a.*, level from emp a
start with mgr is null
connect by mgr = prior empno;

The start with .. connect by clause can be used to select
data that has a hierarchical relationship (usually some sort
of parent->child (boss->employee or thing->parts).

Answer / guest

Retrives rows in hierarchical order.
e.g. select empno, ename from emp where

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