> > and not simply a lock on the pg_constraint table > > In this context, a lock on pg_constraint *is* global, because it will > mean that no one else can be creating an index on some other table. > They'd need to hold that same lock to ensure that *their* chosen > constraint name is unique.
So I am understanding correctly. I think it would be a rare event to have more than one person changing the database structure at the same time. Anyway, the index example is a bad example isn't it? It already takes an lock on pg_class which is just as global. Check constraints and foreign key constraints are two that I can see affected in the manner described. Anyway, my current implementation has constraint names unique to the relation only -- not the namespace, although my locking may be excessive in that area. ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
