"PostgreSQL Bugs List" <pgsql-bugs@postgresql.org> writes:
> Suggested fix: create some empty file in the directory
> if it is used by a namespace.
This was discussed and rejected before --- the problem is not worth the
amount of mechanism that would have to be added to fix it this way.
See the pghackers archives, but I believe the main problem is that a
namespace is not a table and so none of the mechanisms that support file
creation/deletion will work with it.
regards, tom lane