I wrote:
> Gregory Stark <stark@enterprisedb.com> writes:
>> Does the SQL spec actually specify what happens if you provide an
>> non-compliant table definition like this?
> It does not. We could accept expressions there, and pray that the SQL
> committee never extends the spec syntax in a direction incompatible with
> that. That seems like a pretty risky thing to do though.
[ remembering previous discussions more clearly... ] Actually there
is a concrete problem here: unique constraints are supposed to be
represented in the information_schema views, and there is no
spec-compliant way to do that for a constraint on something other than
a column. We'd have to guess at what the SQL committee would do about
that, and the odds of guessing exactly right don't seem encouraging.
regards, tom lane