From: Andreas Joseph Krogh <andreak@officenet.no>
Organization: OfficeNet AS
To: pgsql-sql@postgresql.org
Subject: Constraint question
Date: Thu, 18 May 2006 15:41:53 +0200
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I have the following table:

create table onp_crm_businessfield_company(
businessfield_id integer not null references onp_crm_businessfield(id),
company_id integer not null references onp_crm_relation(id),
is_preferred boolean,
UNIQUE(businessfield_id, company_id)
);


I want a constraint on "is_preffered" so that it's only allowed to be set o=
nce=20
pr. businessfield_id pr. company so that only one businessfield can be=20
preferred for a company. Does anyone have an idea how to enforce this?

=2D-=20
Andreas Joseph Krogh <andreak@officenet.no>
Senior Software Developer / Manager
gpg public_key: http://dev.officenet.no/~andreak/public_key.asc
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