Re: WIP: generalized index constraints

2009/8/21 Jeff Davis <pgsql@j-davis.com>:
> If they include indexes and not constraints, I think we should follow
> the same policy as unique constraints, and create the index and the
> constraint.
>
> The behavior seems a little strange to me, but that's the current
> behavior for unique indexes.

This may be an opportunity to fix it.

The current behaviour seems to be predicated on the unique constraint
being an integral part of the index itself.  While this might be true
from a system catalog point of view (pg_index.indisunique), if a user
says that they want to copy a table's structure INCLUDING INDEXES
EXCLUDING CONSTRAINTS then IMO they've made their intention perfectly
clear.  They'd expect it to create an index sans the unique
constraint.  Ignoring the user's intention and copying the index as-is
(including the unique constraint) would be unfriendly.

Unless the SQL spec demands that we do so?

Cheers,
BJ