Re: CREATE TABLE with REFERENCE

Stephan Szabo wrote:

>On Mon, 28 Jul 2003, kay-uwe.genz wrote:
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>>i've a little problem with two tables and FOREIGN KEYs. I've read about
>>this long time ago, but didn't remember me where. Well, I hope you can
>>help me.
>>
>>I've create two TABLEs "counties" and "cities". "Countries" have a row
>>"capital" is REFERENCEd "cities". "cities" have a row country
>>REFERENCEd "countries", where a save the country the city is placed.
>>
>>And now PG couldn't create the TABLEs, because the referenced table
>>doesn't exists in time of creation. Is there another method of creating
>>than the ALTER TABLE the first table after the second is living?
>>
>>
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>Not really. That's the correct way to make the constraints.
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>>Second question. Is there a method of INSERT INTO both tables VALUES
>>without group them in the same Transaction?
>>
>>
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>You mean insert a row in each table that acts as the pk row for the other?
>
>You could fake it by inserting one in with a NULL for the fk column
>(unless they're both NOT NULL), inserting the other and then updating the
>first. Otherwise I think you need to be running in a single transaction
>(although they could be grouped inside a function or as a trigger for
>example).
>

But isnt' foreign key constraints deferrable inside transactions?
i vaugely remember doing it . istn' it the best way of doing it?
[ if at all it works :-) ]

regds
Mallah.

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