> Thanks for your help on this. The additional column is a varchar2(32)
data
> type. I ran some tests too see the effect on the number of blocks
retrieved
> to satisfy a query. The single column required 360 blocks, whereas the
> concatenated column required 369 blocks. Not much difference, but I
guess
> it all depends on the performance requirement of the application.
>
> Thanks,
>
> Rick Stephenson
>
I wouldn't think that a 2.5% decrease in the number of index blocks
read would justify another index. The 2.5% difference translates to
a smaller overall change in response time, particurlary if the query
must also read table blocks. ie. the index alone cannot satisfy
the query.
Jared
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Received on Tue Aug 10 2004 - 13:28:52 CDT
