Merlin Moncure <mmoncure@gmail.com> writes:
> On Thu, Jul 26, 2012 at 11:02 AM, Mike Christensen <mike@kitchenpc.com> wrote:
>> I don't really think you'd need to decouple the internal column order
>> from what the user sees. A REORDER COLUMNS command should re-build
>> the table with the columns in the specified order.
> That's a controversial point: doing it that way makes reordering of
> large tables highly impractical.
In particular, if the implementation works like that, you hardly need
any system support at all. You can do the equivalent today with a few
SQL commands: create a new table by selecting columns from the old,
drop old table, rename new into place. The universal assumption has
been that REORDER COLUMNS needs to work by just adjusting a few catalog
entries, or it's not worth bothering with.
regards, tom lane
