> -----Original Message-----
> From: Michael Glaesemann [mailto:grzm@seespotcode.net]
> Sent: Wednesday, May 09, 2007 12:14 PM
> To: Dann Corbit
> Cc: Ashish Karalkar; Andrej Ricnik-Bay; Ron Johnson; pgsql-
> general@postgresql.org
> Subject: Re: [GENERAL] Views- Advantages and Disadvantages
>
>
> On May 9, 2007, at 14:02 , Dann Corbit wrote:
>
> > Views can hide important information from the optimizer (especially
> > index information).
>
> Really? AIUI, views-at least in PostgreSQL-are implemented using
> PostgreSQL's rule system: the entire query is rewritten to include
> the view query, and the optimizer sees the rewritten query. What the
> optimizer sees is the same as if the view were inlined in the
> original query.
That is a significant achievement, since many database systems do not
have that ability.