Ivan Voras writes:
> I'm just wondering: in the execution plan such as this one, is the
> "Recheck Cond" phase what it apparently looks like: an additional check
> on the data returned by indexes, and why is it necessary?
Bitmap indexscans are potentially lossy. If the bitmap recording all the
t
On 25/10/2013 11:06, Albe Laurenz wrote:
> Just because there is an entry in the index does not imply that the
> corresponding table entry is visible for this transaction.
> To ascertain that, the table row itself has to be checked.
Understood.
> PostgreSQL 9.2 introduced "index only scan" which
Ivan Voras wrote:
> I'm just wondering: in the execution plan such as this one, is the
> "Recheck Cond" phase what it apparently looks like: an additional check
> on the data returned by indexes, and why is it necessary? I would have
> though that indexes are accurate enough?
>
> cms=> explain ana
Hi,
I'm just wondering: in the execution plan such as this one, is the
"Recheck Cond" phase what it apparently looks like: an additional check
on the data returned by indexes, and why is it necessary? I would have
though that indexes are accurate enough?
cms=> explain analyze select * from users
