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From Øystein Grøvlen <Oystein.Grov...@Sun.COM>
Subject Re: [jira] Updated: (DERBY-1862) Simple hash improves performance
Date Mon, 18 Sep 2006 13:16:08 GMT
Andreas Korneliussen (JIRA) wrote:

> 
> Attached is a patch which uses another approach to improve the SQLEqualsIgnoreCase method.
The patch check the identity and length of the strings to be compared, before doing conversions
to uppercase with english locale. 
> 
> String.toUpperCase(..) with english locale, should return a string with the same number
of characters, and it should therefore be valid to do a check of number of characters before
doing any conversions.

Still, nothing beats using column indexes :-)

Another optimization one could do would be to store the column 
descriptors in a normalize form.  (Maybe they already are).  Then, only 
one of the strings would need to be upper-cased for each comparison.

--
Øystein

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