Re: How efficient are Views

On Thu, 2002-06-13 at 03:02, John Taylor wrote:
> Hi,
>
> I'm thinking about using a view for my application.
>
> However, I'm wondering about how efficient it will be once I have a large amount of data
> loaded.
>
> Are views generated for every access ?
> Are they generated when the underlying data changes ?
>
> Whould it maybe be faster to have a seperate table alongside the base data, and
> generate it via a trigger or stored procedure ?

It depends on your ratio of queries to inserts.  It depends on the size
of your tables and the indexing that you have on them.  It depends on
whether your queries are on subsets or summaries.

On the other hand, there is no reason why queries should necessarily be
slow 'once you have a large amount of data loaded' - that depends on a
lot more database choices than just whether you use a view.

Regards,
                    Andrew.
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