Re: REFERENCES constraint

Cedar,

> 1. Can a column reference more than one table?  (This assumes you use
> a
> single sequence to generate the IDs for both "tbla" and "tblb".  I
> guess
> you would also have the problem of enforcing a unique index.  Say
> what?!  
> A unique index across multiple tables.. absurd :)  eg..
> 
>   CREATE TABLE blah (
>     id int4,
>     f_id int4 REFERENCES tbla (id) REFERENCES tblb (id)
>   )

I'd reccomend, instead, having blah reference tbla and tbla reference
tblb.  It'd have the same effect, without forcing you to monkey around
with custom triggers.

> 2. Can a column reference another column in the same table?  eg..
> 
>   CREATE TABLE bloo (
>     id int4,
>     p_id int4 REFERENCES bloo (id)
>   -- or
>   --p_id int4 REFERENCES (id)
>   )

Er ... why would you want to?

-Josh Berkus

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