Ron Mayer <rm_pg@cheapcomplexdevices.com> writes:
> Would doing something with ctid be even better?
> Or does it have some risks I'm missing. I'm thinking
> something like:
> update table set new_column=[whatever] where ctid<'(10000,1)';
> vacuum;
> update table set new_column=[whatever] where ctid>'(10000,1)' and ctid<'(20000,1');
> vacuum;
> ...
> update table set new_column=[whatever] where ctid>'(180000,1)';
> vacuum;
You are forgetting the fact that an UPDATE in itself changes a row's
ctid.
regards, tom lane
