From: Joe Conway <mail@joeconway.com>
To: Terry Lee Tucker <terry@esc1.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Novice needs help
Date: Tue, 11 Mar 2003 12:59:07 -0800
Message-ID: <3E6E4E1B.2080605@joeconway.com> (raw)
In-Reply-To: <3E6E2139.5060903@esc1.com>
References: <3E6E2139.5060903@esc1.com>
Terry Lee Tucker wrote:
> I have loaded over 29,000 customer records into a database. I'm trying
> to apply a referential foreign key that validates the country code and
> the province code in another table. It won't work because somewhere in
> that 29,000 records there is a province code or country code that
> doesn't match. Is there a way to use a select statement to find out
> which customer records has the invalid data? Here is the partial table
> layout:
>
> cust province
> -------- -------
> country ===> country
> province ===> code
>
If I understand correctly, something like this should work (not tested):
select c.country, c.province from cust c left join province p on
c.country = p.country and c.province = p.code where p.country is null;
or alternatively
select c.country, c.province from cust c where not exists (select 1 from
province p where p.country = c.country and p.code = c.province);
Joe
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: pgsql-sql@postgresql.org
Cc: mail@joeconway.com, terry@esc1.com
Subject: Re: Novice needs help
In-Reply-To: <3E6E4E1B.2080605@joeconway.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox