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From tom <thomas.vat...@network-inventory.de>
Subject Re: order by
Date Wed, 01 Mar 2006 08:35:38 GMT
Jeffrey Lichtman <swazoo@...> writes:

> 
> 
> >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@...
>                                  Check out Swazoo Koolak's Web Jukebox at
>                                  http://swazoo.com/ 
> 
> 


Yes, you are right, the index is corrupted, I just found that the problem is not
reproducible with other datasets. I create the datasets by importing spreadsheet
data by am import program. The problematic dataset has 1300 records. I now found
that near the end of this import error messages are listed in the background. I
tried with a smaller spreadsheet with 108 records and here everything is ok. Now
I'll find out why import of larger spreadsheet has problems. 


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