where condition based on bind variables - sql

Question

I want a different set where condition to be executed on a query based on a bind variable in Oracle sql .
Here is what I have tried
Table a contains
a_id primary key
a_role varchar2(10)
SELECT *
FROM a
WHERE a_role IN ('approved','rejected' , 'needInfo') AND
:bind = 'new' OR
:bind != 'new AND
a_role IN ('complete') AND
:bind = 'approved' OR
:bind != 'approved'
In short i am trying to select roles based on current role which I will pass in bind variable. I want something like
if(:bind = 'new')
{select 'approved' , 'rejected' , 'needInfo' }
else if (:bind = 'approved')
{ select 'complete' }
Thanks ,
Puneet

Answer 1

You have both AND and OR conditions mixed in your statement, and they may not be interpreted as you wanted. Additionally, it looks like the two comparisons to a_role should be OR'd together rathen than AND'd. Try the following:
SELECT *
FROM a
WHERE (:bind = 'new' AND
(a_role IN ('approved','rejected' , 'needInfo')) OR
(:bind = 'approved' AND
a_role IN ('complete'))
Share and enjoy.

Answer 2

I can't be certain because I'm not clear what your original query is trying to do - but it should be something like this, assuming your running in sqlPlus:
variable bind varchar2
bind := 'new'
SELECT *
FROM a
WHERE (:bind = 'new' AND a_role IN ('approved','rejected' , 'needInfo'))
OR (:bind = 'approved' AND a_role IN ('complete'))
This article explains thins fairly neatly