Pavan Deolasee wrote:
ISTM that the PD_ALL_VISIBLE flag and the visibility map bit can be set at the end of pruning operation if we know that there are only tuples visible to all transactions left in the page.
Right.
The way pruning is done, I think it would be straight forward to get this information.
Is it? I thought about that a bit while writing the patch, but didn't see any obvious way to do it. Except by adding a loop through all tuples on the page, but that's extra overhead. I think we're looping through all tuples in the pruning, but it's not quite obvious.
If you see a straightforward way, please submit a patch! -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
