Re: visibility maps and heap_prune

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