I have the following query in oracle. I want to convert it to PostgreSQL form. Could someone help me out in this,
SELECT user_id, user_name, reports_to, position
FROM pr_operators
START WITH reports_to = 'dpercival'
CONNECT BY PRIOR user_id = reports_to;
A something like this should work for you (SQL Fiddle):
WITH RECURSIVE q AS (
SELECT po.user_id,po.user_name,po.reports_to,po.position
FROM pr_operators po
WHERE po.reports_to = 'dpercival'
UNION ALL
SELECT po.user_id,po.user_name,po.reports_to,po.position
FROM pr_operators po
JOIN q ON q.user_id=po.reports_to
)
SELECT * FROM q;
You can read more on recursive CTE's in the docs.
Note: your design looks strange -- reports_to contains string literals, yet it is being comapred with user_id which typicaly is of type integer.
WITH RECURSIVEand common table expressions.