From: | Jan Wieck <JanWieck(at)Yahoo(dot)com> |
---|---|
To: | Luis Sousa <llsousa(at)ualg(dot)pt> |
Cc: | Richard Huxton <dev(at)archonet(dot)com>, Filipe Bonjour <fbonjour(at)urbanet(dot)ch>, pgsql-sql(at)postgresql(dot)org |
Subject: | Re: Can arrays reference primary keys in CREATE TABLE? |
Date: | 2003-05-19 17:40:20 |
Message-ID: | 3EC91704.1080109@Yahoo.com |
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Thread: | |
Lists: | pgsql-sql |
Luis Sousa wrote:
> Richard Huxton wrote:
>
>> On Friday 09 May 2003 10:21 pm, Filipe Bonjour wrote:
>>
>>
>>> Hi,
>>>
>>> I'm a rather new SQL user, and I found interesting that you can
>>> use "references" to make sure that a value inserted in a table is a
>>> primary key from another table. Something like:
>>>
>>
>>
>> Yep - referential integrity is vital.
>>
> I used a trigger to get referential integrity.
> So, on update or insert, it fires the function that's going to read the
> new array and check if really exists on the other table
And what happens on UPDATE or DELETE to the primary key table?
You used a trigger to check something, but unless you have a full set of
said triggers and they do the locking as well, you do not have
referential integrity.
Jan
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