Best SQL Query

Hi Everybody,

I have a procedure sp1 which receives a parameter p_cust_id.

   If the parameter p_cust_id is null then My query has to fetch all the customers.

   If param p_cust_id is not null then
My query has to fetch only the specified customer record.

I have 3 queries which can do the same but I am foxed regarding the fact which the best one.
Note: p_cust_id is defined as number(4)

They are
Query 1

SELECT cust_name
FROM customer
WHERE cust_id = Nvl(p_cust_id,cust_id)

Query 2

SELECT cust_name
FROM customer
WHERE cust_id LIKE Nvl(p_cust_id,'%')

Query 3

SELECT cust_name
FROM customer
WHERE (cust_id = p_cust_id

       OR p_cust_id IS NULL)

All the three use the index but which is the best?

Regards
Rajs(TechCell)

-----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own Received on Sat Dec 12 1998 - 00:14:08 CST