Re: update query taking too long

["A. Kretschmer" <andreas(dot)kretschmer(at)schollglas(dot)com>]

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));
UPDATE 2
test=*# select * from foo;
 id |    mail     | domain
----+-------------+---------
  1 | foo(at)foo(dot)tld | foo.tld
  2 | bar(at)bar(dot)tld | bar.tld
(2 rows)


(without the @ in the domain...)


Andreas
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Andreas Kretschmer
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