Re: Index on date-fields with NULL values
From: Michael Willer <no_at_spam.please>
Date: Sun, 06 Jul 2003 17:53:04 +0200
Message-ID: <3f084619$0$24671$edfadb0f_at_dread14.news.tele.dk>
Date: Sun, 06 Jul 2003 17:53:04 +0200
Message-ID: <3f084619$0$24671$edfadb0f_at_dread14.news.tele.dk>
Aad Aldus wrote:
> Ik have created an index on a date field.
> 99% of all data in the table has a filled in date. 1 % is NULL
> When I do a select with clause ... WHERE ADATE IS NULL,
> Oracle does not use the index.
>
> Is this correct? or How can I force Oracle to use the index.
>
> Kind reagrds,
> Aad.
>
> PS: I am using Oracle 8.1.7 and 9.2
>
>
Given that 99% of the table-data is returned by the query a Full table
scan is actually faster than using an index.
Michael Willer
Oracle/J2EE architect
Cyber Com Consulting a/s
Received on Sun Jul 06 2003 - 17:53:04 CEST