Posted by drawnai on 04/24/06 10:58

Erland Sommarskog wrote:
> David Portas (REMOVE_BEFORE_REPLYING_dportas@acm.org) writes:
> > In your example you try to force a particular execution plan onto your
> > code using an INDEX hint. But there is absolutely no reason why SQL
> > Server should always be required to implement a hint. Indexes are
> > intended as an optimization tool - they are not supposed to affect
> > logical behaviour of code.
>
> I only like to enforce this: if the result of a query is dependent on
> the presense of an index, the result of the query is undefined (or there
> is a plain bug). The task of indexes is to decrease execution times, but
> they should not affect the outcome of a query.

I'm prepared to put up with checking a view queries once every new
generation
of SQL server, for an e-commerce site that will run on a laptop, rather
than
pay half a million quid for hardware licence fees, just to do it the
hard way.

>
> Of course, by adding an index hint you at least ensure that they query
> will fail would the index be dropped. Then again, if someone changes
> the index, you lose anyway.
>
>
>
> --
> Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se
>
> Books Online for SQL Server 2005 at
> http://www.microsoft.com/technet/prodtechnol/sql/2005/downloads/books.mspx
> Books Online for SQL Server 2000 at
> http://www.microsoft.com/sql/prodinfo/previousversions/books.mspx

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