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references versus foreign keys

This is a discussion on references versus foreign keys within the pgsql Novice forums, part of the PostgreSQL category; --> Maybe this is too much of a noob question but bear with me. I'm assuming that I have a ...


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  #1 (permalink)  
Old 04-17-2008, 10:38 PM
Tom Allison
 
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Default references versus foreign keys

Maybe this is too much of a noob question but bear with me.

I'm assuming that I have a choice between
CREATE TABLE (..) REFERENCES other
and
CREATE TABLE (..) FOREIGN KEY () REFERENCES other
What is the differences between the two and why/when would I choose one over the
other?

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  #2 (permalink)  
Old 04-17-2008, 10:38 PM
Tom Lane
 
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Default Re: references versus foreign keys

Tom Allison <tallison@tacocat.net> writes:
> Maybe this is too much of a noob question but bear with me.
> I'm assuming that I have a choice between
> CREATE TABLE (..) REFERENCES other
> and
> CREATE TABLE (..) FOREIGN KEY () REFERENCES other
> What is the differences between the two and why/when would I choose one over the
> other?


You have to use the more verbose syntax to establish a multi-column
reference. For single-column keys it doesn't matter which way you
do it.

regards, tom lane

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