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On Mon, 13 May 2002 23:30:23 GMT, "Alex Ivascu" <alex_at_ivascu.com>
wrote:
>Ouch!
>
>I did a simple test w/ 150K rows. It does seem to make a difference (small
>one), but it does. Wonder why?
Are the numbers the same for both COUNT() results? I thought COUNT(*) counted nulls too, while COUNT(column_name) omitted nulls.
Searching for "count(*) and nulls" also turns up some discussion of performance differences depending on whether bitmap indexes are used or not.
John
-- Got an Oracle database question? Try the search engine for the database docs at: http://tahiti.oracle.com/ The opinions expressed above are mine and do not necessarily reflect those of Oracle Corporation.Received on Mon May 13 2002 - 23:53:32 CDT