PG Bug reporting form <noreply@postgresql.org> writes:
> When creating a domain with a NOT NULL constraint, the conkey field in
> pg_constraint remains empty. This is inconsistent with table-level NOT
> NULL constraints, which correctly populate the conkey field.
I do not think this is a bug. The system catalog documentation says
conkey int2[] (references pg_attribute.attnum)
If a table constraint (including foreign keys, but not
constraint triggers), list of the constrained columns
So (a) this is not a table constraint, and (b) a domain does not have
columns.
regards, tom lane
