Views & nested queries vs joins

While I know that in a regular query a JOIN is more expensive than a
nested query, is the same true of the query that comprises a view?

I could experiment and find out, but performance measurements are
still a bit of an unknown for me...was hoping someone might have an
off the cuff answer :)

Tyler

On Fri, 25 Apr 2008 23:45:46 +0200, Logos <tyler.style@gmail.com> wrote:

> While I know that in a regular query a JOIN is more expensive than a
> nested query,

Whivh is untrue.... It depends on circumstance, and usually the JOIN is
less 'expensive'.

> is the same true of the query that comprises a view?

Erm, it's nice to have a view of often accessed and seldomly changed data.

> I could experiment and find out, but performance measurements are
> still a bit of an unknown for me...was hoping someone might have an
> off the cuff answer :)

Give us some real example to give an educated answer. but performance is
sometimes quite tricky, and dependant on a lot of variables.
--
Rik Wasmus

Logos wrote:
> While I know that in a regular query a JOIN is more expensive than a
> nested query,
What you "know" is in fact wrong. It it almost ALWAYS the other way round.

On Apr 26, 3:28 am, "Paul Lautman" <paul.laut...@btinternet.com>
wrote:
> Logos wrote:
> > While I know that in a regular query a JOIN is more expensive than a
> > nested query,
>
> What you "know" is in fact wrong. It it almost ALWAYS the other way round.

I seem to be reading a fair number of articles which seem to
contradict each other on this...blah. Back in the day (wow, 10yrs
ago!) I recall being taught that joins were more expensive than
subqueries. Things seem to be more confusing now :P

Perhaps to sum things up more succintly for my question: Are the
queries comprising views handled any differently than a normal query?

Tyler