Re: ** SQL QUERY TUNING

On 17-Apr-98 16:08:03 Jürgen Kling wrote:

>Who can help me to optimize the following SQL-Statement

>select * from table
>where tab_column = 1
> or tab_column is null

>Thje column TAB_COLUMN having an index, but ORACLE cant't use it. Thus
>Oracle do an Full Table scan.

Hello!

The problem is that nulls are not indexed so that your query cannot use the index.
Eventually a bitmap index can be used. I don't have Oracle available right now to check though...

Hope that helps,
Lothar

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Lothar Armbrüster       | lothar.armbruester_at_rheingau.netsurf.de
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