On ons, 2012-01-18 at 18:17 -0500, Robert Haas wrote: > I agree with Peter that we should have we should have CHECK ONLY. > ONLY is really a property of the constraint, not the ALTER TABLE > command -- if it were otherwise, we wouldn't need to store it the > system catalogs, but of course we do. The fact that it's not a > standard property isn't a reason not to have proper syntax for it.
Clearly, we will eventually want to support inherited and non-inherited constraints of all types. Currently, each type of constraint has an implicit default regarding this property: check - inherited not null - inherited foreign key - not inherited primary key - not inherited unique - not inherited exclusion - not inherited As discussed above, we need to have a syntax that is attached to the constraint, not the table operation that creates the constraint, so that we can also create these in CREATE TABLE. How should we resolve these different defaults? Also, in ALTER TABLE, if you want to add either an inherited or not inherited constraint to a parent table, you should really say ALTER TABLE ONLY in either case. Because it's conceivably valid that ALTER TABLE foo ADD CHECK () NOINHERIT would add an independent, not inherited check constraint to each child table. So, there are all kinds of inconsistencies and backward compatibility problems lurking here. We might need either a grand transition plan or document the heck out of these inconsistencies. -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
