public inbox for [email protected]  

help / color / mirror / Atom feed

From: Erik Thiele <[email protected]>
To: Achilleus Mantzios <[email protected]>
Cc: [email protected]
Subject: Re: special integrity constraints
Date: Mon, 22 Mar 2004 11:26:59 +0100
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
	<[email protected]>

On Mon, 22 Mar 2004 12:13:29 +0200 (EET)
Achilleus Mantzios <[email protected]> wrote:

> O kyrios Erik Thiele egrapse stis Mar 22, 2004 :
> 
> Did you check out the DEFERRABLE option on the constraint?
> 

DEFERRABLE
NOT DEFERRABLE

This controls whether the constraint can be deferred. A constraint that
is not deferrable will be checked immediately after every command.
Checking of constraints that are deferrable may be postponed until the
end of the transaction (using the SET CONSTRAINTS command). NOT
DEFERRABLE is the default. 

!!!! Only foreign key constraints currently accept
this clause. All other constraint types are not deferrable. !!!!

my constraint is not a foreign key constraint....

cya!
erik

> > hi,
> > 
> > i have two tables
> > 
> > create table a (x integer);
> > create table b (y real);
> > 
> > i have the special constraint that the sum of the number of rows in
> > table a plus the number of rows in table b must be even.
> > 
> > so there is a posibility of adding one element to a and one element
> > to b, and again the constraint is met.
> > 
> > but this of course does not work, since between adding the element
> > to a and adding the element to b, the constraint is not met.
> > 
> > so i cannot use a trigger.
> > 
> > what i need is the execution of a check procedure at commit time. is
> > that somehow possible?
> > 
> > my database has much more tables than just a and b, and most time
> > the other tables are modified and not a or b, so it would be nice to
> > execute the constraint checking procedure only if a or b was
> > modified.
> > 
> > yes :) this question i asked in my former mail too, but I think it
> > looked like there was a workaround and my problem was wrong. so i
> > created this new kind of problem here to make things clearer.
> > 
> > 
> > cu
> > Erik
> > 
> > 
> > 
> 
> -- 
> -Achilleus
> 


-- 
Erik Thiele
Horst Thiele Maschinenbau-Hydraulische Geräte GmbH
Im Kampfrad 2 - 74196 Neuenstadt
Tel.: 07139/4801-19
Fax.: 07139/4801-29
email: [email protected]
Internet: http://www.thiele-hydraulik.de/

view thread (13+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: Re: special integrity constraints
  In-Reply-To: <[email protected]>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox