David J N Begley <d.begley@uws.edu.au> writes:
> So... why can I assign NULL to a composite type column in a table but not to a
> composite type variable in PL/pgSQL? Is there any way to force that "out"
> composite type variable to be NULL?
In general the distinction between a true null composite value and a
row-of-nulls is not made very cleanly in PG. I'd be inclined to
deprecate the former --- you cannot enter such a thing as a row of a
table, for example, and that is the basic property that any rowtype
ought to have no?
In short, don't do that.
regards, tom lane