Re: index on foreign key

Hello Marc,

In general, yes. However, if the index is not needed to support an access path, and if the parent table is never updated during normal operation such that a shared lock would be taken against the child table in the absence of the index, then the index should NOT be present in order to avoid the index maintenance that would be required for DML on the table. Any risk of unexpected updates on the parent table taking a shared lock on the child can be excluded using the ALTER TABLE DISABLE TABLE LOCKS statement.

Regards,
Steve Adams

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On Thu, 08 Jun 2000 05:24:35 -0700, mcomer <mcomer2NOmcSPAM_at_hotmail.com.invalid> wrote:

>In an Oracle database, should all foreign key columns have
>indexes?
>
>Marc
>
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Received on Fri Jun 09 2000 - 00:00:00 CDT