Re: index
Date: Mon, 28 Jul 2008 20:03:32 -0700 (PDT)
Message-ID: <f08bba46-7bd1-443e-97fd-fe07a9ec1a3f_at_25g2000hsx.googlegroups.com>
On Jul 29, 10:45 am, "Brian Selzer" <br..._at_selzer-software.com> wrote:
> "David BL" <davi..._at_iinet.net.au> wrote in message
> > Physical duplication of data can be appropriate to increase read
> > performance at the expense of write performance. Indeed any secondary
> > index is a form of redundancy that hurts write performance.
>
> Boosting read performance can be accomplished just as well with a covering
> non-clustered index as with a clustered index.
That is not always true. There could be an application involving a query that uses the non-clustered index and also needs *all* the additional data in the record. The additional seeks could mean the read performance doesn’t meet the requirements. Received on Tue Jul 29 2008 - 05:03:32 CEST