On Wed, Jul 22, 2020 at 11:13 AM Daniel Verite <daniel@xxxxxxxxxxxxxxxx> wrote:
Mohamed Wael Khobalatte wrote:
> We lock the table as a precaution, with the understanding that we are
> undergoing a "small" downtime to finish replacing the int id by the new
> bigint
Ah, sorry I overlooked that most row updates are done
pre-transaction in a preliminary step:
/* in batches, we update all the rows to new_id = id */
No worries. I suppose the answer to the original question, which is how to avoid a table scan when adding a primary key constraint to a newly backfilled column is "there is no way"? Downtime might be at least as long as the table scan.
