From: | Robert Osowiecki <magic(dot)robson(at)rassun(dot)art(dot)pl> |
---|---|
To: | pgsql-hackers(at)postgresql(dot)org |
Subject: | Views and unique indicies optimisation |
Date: | 2003-02-10 19:12:01 |
Message-ID: | 8646.1044902158.zmok@sepulka.mimuw.edu.pl |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Here's an example:
create view master_detail
as select * from master
left join detail on (master.detail_key=detail.key);
I noticed that PostgreSQ performs join even when I execute
select some_master_fields from master_detail;
but there exists an unique index on detail.key, so above query
gives the same result as
select some_master_fields from master;
but with much loss in performance, of course.
This problem emerged when I replaced renundant table in poorly
designed database with two tables, view and set of rules.
I thought that I was very clever, because I didn't have to
replace any code in applications using this database, but
it seems that there's always a catch...
May I have hope that such optimisation will be included in
TODO list in near future?
--
<><><><><><><><><><><><><><><><><><><><><>
<> magic(dot)robson(at)rassun(dot)art(dot)pl <>
<> http://rainbow.mimuw.edu.pl/~robson <>
<><><><><><><><><><><><><><><><><><><><><>
From | Date | Subject | |
---|---|---|---|
Next Message | Peter Eisentraut | 2003-02-10 19:12:44 | Re: PGP signing releases |
Previous Message | Tom Lane | 2003-02-10 19:07:46 | Re: Status report: regex replacement |