~
Haisheng Yuan
On Wed, Dec 20, 2017 at 9:43 PM, Jeff Janes wrote:
> On Tue, Dec 19, 2017 at 11:55 AM, Haisheng Yuan wrote:
>
>> Hi hackers,
>>
>> This is Haisheng Yuan from Greenplum Database.
>>
>> We had some query in production showing that planner favors se
Robert, you are right. The new formula serves Greenplum better than the
original formula, because our default random page cost is much higher than
Postgres. We don't want random cost always dominates in the final cost per
page.
~ ~ ~
Haisheng Yuan
On Wed, Dec 20, 2017 at 12:25 PM, Robert
Hi hackers,
This is Haisheng Yuan from Greenplum Database.
We had some query in production showing that planner favors seqscan over
bitmapscan, and the execution of seqscan is 5x slower than using
bitmapscan, but the cost of bitmapscan is 2x the cost of seqscan. The
statistics were updated and
