Creating trees, step - by - step

Question

anyone know how to make a tree easily or have some step by step instructions.
i am trying to create a tree that will show project number then level down to task number and then subtask number.
projects , tasks, and subtasks are on seperate tables.
Edited by: KySarge1981 on Aug 16, 2010 10:40 AM

Answer 1

A tree is based on a single query that returns a hierarchy. You will need to work your tables into one query - using a union. You can create a default tree, just using the EMP table, accepting the defaults and then replace the query with your own. The example tree query below selects all the departments and then all the employees within those departments. You would need to craft a similar query to output your data to contain the hierarchy that you described. You can run it in SQL Commands to view the output you will need.
<pre>select case when connect_by_isleaf = 1 then 0
when level = 1 then 1
else -1
end as status,
level,
d as title,
null as icon,
r as value,
null as tooltip,
null as link
from (select 'Employee: ' || ename d, empno r, deptno parent from emp
union all
select 'Department: ' || dname d, deptno r, null parent from dept)
start with parent is null
connect by prior r = parent
order siblings by d</pre>
-- Sharon