Re: View vs function - Mailing list pgsql-performance

From Bruno Wolff III
Subject Re: View vs function
Date
Msg-id 20050321042720.GA27098@wolff.to
Whole thread Raw
In response to View vs function  (Keith Worthington <KeithW@NarrowPathInc.com>)
Responses Re: View vs function  (Neil Conway <neilc@samurai.com>)
List pgsql-performance
On Sun, Mar 20, 2005 at 22:39:57 -0500,
  Keith Worthington <KeithW@NarrowPathInc.com> wrote:
> Hi All,
>
> I have been reading about set returning functions.  What I would like to
> know is is there a performance advantage in using SRFs versus querying a
> view.  Assuming the underlying SQL is the same for the view vs the
> function except for the WHERE clause which of these would you expect to
> be faster?  Or does the planner realize all this...

In general you are going to be better off with a view, since the planner
knows what the view is doing and there may be some optimizations it
can make. Functions are just black boxes to the planner.

>
> SELECT * FROM view_big_query WHERE column1 = 1234;
>
> SELECT * FROM func_bug_query(1234);
>
> --
> Kind Regards,
> Keith
>
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