Re: multi column foreign key for implicitly unique columns - Mailing list pgsql-sql

From Tom Lane
Subject Re: multi column foreign key for implicitly unique columns
Date
Msg-id 1535.1092845917@sss.pgh.pa.us
Whole thread Raw
In response to Re: multi column foreign key for implicitly unique columns  (Richard Huxton <dev@archonet.com>)
Responses Re: multi column foreign key for implicitly unique columns  (Jan Wieck <JanWieck@Yahoo.com>)
List pgsql-sql
Richard Huxton <dev@archonet.com> writes:
> * Allow multiple unique constraints to share an index where one is a 
> superset of the others' columns.

> That way you can mark it unique without having the overhead of multiple 
> indexes.

That just moves the uncertain-dependency problem over one spot, ie, it's
the fabricated unique constraint that you can't pin down the
requirements for.
        regards, tom lane


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