On Mon, Jun 1, 2009 at 9:49 PM, Jeff Davis <pg...@j-davis.com> wrote: > > > NUMERIC(x, y) comes to mind, although that might be a more dangerous > case. If you turn a NUMERIC(5,0) into a NUMERIC(5,1), then '1.2' may be > stored as either '1' or '1.2' depending on whether you did the insert > before or after the change. That's because, with NUMERIC, it's not > really a constraint, but a rule for rounding.
Well it's not like rewriting the table is going to accomplish anything though... > There may be other interesting cases involving constraints. For > instance, if you have CHECK(i < 200), you should be able to add CHECK(i > < 1000) without an exclusive lock or recheck. Then, with an exclusive > lock, you can remove the original tighter constraint, but at least it > wouldn't have to recheck the entire table. We have the infrastructure for this kind of check actually, it's the same kind of thing we do for partition exclusion... -- greg -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers