On Fri, 2008-07-11 at 09:55 -0500, Kevin Grittner wrote: > > Alvaro Herrera <alvherre@xxxxxxxxxxxxxxxxx> writes: > >>> Ow Mun Heng wrote: > >>> If it were this simple a change, I'm not certain why (I believe) PG > >>>is checking each and every row to see if it will fit into the new column > >>> definition/type. > >Because the code that does the ALTER TYPE is very generic, and it > > doesn't (yet) have an optimization that tells it to skip the check > > and the possible table rewrite in the cases where it's obviously not > >needed(like this one). > If there's some low-hanging fruit here, +1 for getting that. I just tested this out and everything seems to be working fine. (cross fingers - for now and if I do report back, it means we've crashed and burned, but as of now... the low hanging fruit is tasty) This 2 sec change is much preferred over the 3+ hour per table. I agree with Tom that this is not useful in _all_ cases and may seem to look like a hack, but it really isn't. Given that the condition that we're expaning the min length rather than the opposite, it should be pretty safe. Guys(/gals) Thanks very much for brightening up a dreadry Monday morning.
