Re: Impact of views on performances

Hi.

1. Beware of "nonmergeable views" - it may degrade your performance. Check Oracle documentation.
2. In theory your query and view definitions will be megred and analyzed as one BIG query, so you are not supposed to have performance problems with views. However we are not living in perfect world - so that merge is not always performed ( see "nonmergeable views" ). At "my" installation we got a number of such problems - so be prepared.

  HTH. Michael.
In article <38a24a55_at_news.vo.lu>,
  "michel parisse" <michel.parisse_at_advalvas.be> wrote:
> I want to use views to isolate code from changes of my database
schema; Yet
> I am told that views will have a negative impact on performance with
the
> growing size of my database (today with the largest table at 150000
records,
> but growing). Further, when I have index defined on the tables that
I am
> planning to access through views, will these indexes continue to be
used?
>
> Any idea of impact or where to look for in depth information?
>
> Michel & Véronique Parisse
>
>

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Before you buy. Received on Fri Feb 11 2000 - 12:39:48 CST