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From Jeffrey Lichtman <swa...@rcn.com>
Subject Re: order by
Date Wed, 01 Mar 2006 04:25:34 GMT

>I have made a test and dropped the composite index, and now the
>sorting is ok, regenerated the index and sorting is as described
>in my first problem report.
>
>tom

It seems likely that the optimizer is using the index as a 
sort-avoidance strategy. That is, it is recognizing that the index is 
in the same order as the "order by" clause, so it's doing an index 
scan instead of using the sorter. Now, I don't know why this in 
itself would cause the problem you're seeing, since as you've 
described it the index should be in the right order. Maybe there's 
something wrong with the index.


                        -        Jeff Lichtman
                                 swazoo@rcn.com
                                 Check out Swazoo Koolak's Web Jukebox at
                                 http://swazoo.com/ 


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