Re: Indexing NULL values

From: Chris Day <chris.day_at_rdbms.freeserve.co.uk>
Date: Fri, 16 Mar 2001 12:19:52 +0000
Message-ID: <3AB204E8.BC8CF77A@rdbms.freeserve.co.uk>

Mike,

bitmap indexes do include NULL.
B-tree indexes do not include NULL

Chris

Mike Fotiou wrote:
>
> Hi,
>
> Is there any way to index null values in Oracle? Does the BITMAP type
> index include NULL values? We have several searches which use IS NULL/IS
> NOT NULL conditions. Currently, the Table Scan that Oracle uses is killing
> query performance. These fields do not really lend themselves to default
> values (e.g. a closing date). In SQL Server, there is the ability to
> include NULLS when the index is built. Is there any such feature in Oracle
> 8/8i?
>
> Mike
Received on Fri Mar 16 2001 - 06:19:52 CST