Help regarding CONNECT BY PRIOR AND LEVEL

Question

Hi
I need to retreive all the employees that are at the least level under a particular employee. Assume basic emp table.
I have been using CONNECT BY PRIOR
select mgr,empno,ename, level from emp
start with empno=7839
connect by prior empno=mgrOUTPUT:
MGR     EMPNO     ENAME     LEVEL
     7839     KING     1
7839     7566     JONES     2
7566     7788     SCOTT     3
7788     7876     ADAMS     4
7566     7902     FORD     3
7902     7369     SMITH     4
7839     7698     BLAKE     2
7698     7499     ALLEN     3
7698     7521     WARD     3
7698     7654     MARTIN     3
7698     7844     TURNER     3
7698     7900     JAMES     3
7839     7782     CLARK     2
7782     7934     MILLER     3The Output i require should be
MGR     EMPNO     ENAME     LEVEL
7788     7876     ADAMS     4
7902     7369     SMITH     4
7698     7499     ALLEN     3
7698     7521     WARD     3
7698     7654     MARTIN     3
7698     7844     TURNER     3
7698     7900     JAMES     3
7782     7934     MILLER     3Also if i change the empno then i need to get only the employees under that employee only.
Thanks in Advance,
G.Vamsi Krishna

Answer 1

oracle_for_dude wrote:
can you explain what is this query doing
SQL> select  mgr,empno,ename, level
2  from    emp
3  where   level  > 2
4  start with  empno = 7566
5  connect by  prior empno = mgr;
MGR      EMPNO ENAME           LEVEL
7788       7876 ADAMS               3
7902       7369 SMITH               37566 in scott.emp table is employee_id of JONES, It's displaying the selected columns for all the employees in the sub-tree starting with Jones, not including Jones (who is at LEVEL=1) and the people who report directly to Jones (LEVEL=2).
>
>
Thanks in advance