Building tree structure

Question

Hi all,
Sorry if this is a wrong place to post.
I want to build a tree structure(or tree grid) using a table emp
by emp table structure is id, pid, emp_name,emp_num, emp_role
now I want to build a hierarchial tree structure where id is primary key
and my table extends upto 4 levels like
id--pid
1 -- 0
2 -- 1
3 -- 2
4 -- 3
5 -- 0
6 -- 1
I want to build a structure some thing like
root
+ john 2349 manager
-mike 1234 analyst
-andrew 1222 clerk
+Jenn         5678   manager
can somebody help me please....

Answer 1

using standard EMP table
SQL> select lpad(' ',3*level,' ')||ename name, empno, job
  2  from emp
  3  connect by prior empno = mgr
  4  start with mgr is null;
NAME                                EMPNO JOB
   KING                              7839 PRESIDENT
      JONES                          7566 MANAGER
         SCOTT                       7788 ANALYST
            ADAMS                    7876 CLERK
         FORD                        7902 ANALYST
            SMITH                    7369 CLERK
      BLAKE                          7698 MANAGER
         ALLEN                       7499 SALESMAN
         WARD                        7521 SALESMAN
         MARTIN                      7654 SALESMAN
         TURNER                      7844 SALESMAN
         JAMES                       7900 CLERK
      CLARK                          7782 MANAGER
         MILLER                      7934 CLERK
14 rows selected.Max
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