RE: function index for like '%string%'

From: Hillman, Alex <Alex.Hillman_at_usmint.treas.gov>
Date: Fri, 01 Jun 2001 14:17:52 -0700
Message-ID: <F001.00318CA1.20010601141108@fatcity.com>

index is not used because you have leading % in the like predicate.

Alex Hillman

-----Original Message-----
Sent: Friday, June 01, 2001 5:09 PM
To: Multiple recipients of list ORACLE-L

I've created a function index for lower(column_name). However the query does
a like comparison rather than equality so the index isn't used. Is there a way to create a function index for this?

Here's the index and query:

create index fx1_auth_users
on auth_users (lower(current_email)
tablespace app01_midx ;

select current_email from auth_users
where lower(current_email) like '%datsit.com%' ;

Thanks much,
Suzy
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Please see the official ORACLE-L FAQ: http://www.orafaq.com
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Author: Suzy Vordos
INET: lvordos_at_datsit.com

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Please see the official ORACLE-L FAQ: http://www.orafaq.com
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Author: Hillman, Alex
INET: Alex.Hillman_at_usmint.treas.gov

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