Here is an idea ...
Create a function that returns NULL if the value is null or any other acceptable value that can be ignored. And the function should return valid values otherwise. Then create a function based index on this and see if that helps you.
To put in other words, you are merely indexing a subset of rows that match your criteria, while ignoring others that you don't want to deal with.
Raj
-------------------------------------------------------------
Rajendra dot Jamadagni at espn dot com
Any views expressed here are strictly personal.
QOTD: Any clod can have facts, having an opinion is an art !!
-----Original Message-----
From: DENNIS WILLIAMS [mailto:[EMAIL PROTECTED]]
Sent: Thursday, March 27, 2003 9:34 PM
To: Multiple recipients of list ORACLE-L
Subject: RE: index on null column
AK
Yes, it will benefit the non-null records. Just remember that the null
values aren't indexes.
Dennis Williams
DBA, 40%OCP, 100% DBA
Lifetouch, Inc.
[EMAIL PROTECTED]
-----Original Message-----
Sent: Thursday, March 27, 2003 5:19 PM
To: Multiple recipients of list ORACLE-L
I have a table with column A. there are 1000000 records in table out of
which 500o records has not null in column A rest are null.
if i created an index on A, will it benefit .
thanks,
ak
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