Re: update query taking too long

From: Chris <dmagick(at)gmail(dot)com>
To: "A(dot) Kretschmer" <andreas(dot)kretschmer(at)schollglas(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: update query taking too long
Date: 2007-06-28 06:37:43
Message-ID: 46835737.8090307@gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

A. Kretschmer wrote:
> am Thu, dem 28.06.2007, um 16:16:50 +1000 mailte Chris folgendes:
>> Is there a better way to write the update? I thought about something
>> like this (but couldn't get it working - guess I don't have the right
>> syntax):
>>
>> update t1 set domainname=(select id, SUBSTRING(emailaddress FROM
>> POSITION('@' IN emailaddress)) from table t2) AS t2 where t1.id=t2.id
>
> test=# select * from foo;
> id | mail | domain
> ----+-------------+--------
> 1 | foo(at)foo(dot)tld |
> 2 | bar(at)bar(dot)tld |
> (2 rows)
>
> test=*# update foo set domain=SUBSTRING(mail FROM (POSITION('@' IN
> mail)+1));

That's what my original query is (apart from the +1 at the end) ;)

I was just trying to approach it differently with the other attempt.

--
Postgresql & php tutorials
http://www.designmagick.com/

In response to

Browse pgsql-performance by date

  From Date Subject
Next Message Richard Huxton 2007-06-28 06:39:46 Re: update query taking too long
Previous Message A. Kretschmer 2007-06-28 06:28:26 Re: update query taking too long