On Sun, Mar 5, 2017 at 11:32 PM, Ashutosh Bapat
wrote:
>> I think there have been
>> previous discussions of switching over to the practice for which you
>> are advocating here, but my impression (without researching) is that
>> the current practice is more like what Rushabh did.
>
> I am not sure
>
>
> I understood you reasoning of why startup_cost = input_startup_cost and not
> input_total_cost for aggregation by sorting. But what I didn't understand is
> how come higher startup cost for aggregation by sorting would force hash
> aggregation to be chosen? I am not clear about this part.
Se
Thanks Ashutosh & Robert for the explanation.
On Mon, Mar 6, 2017 at 10:02 AM, Ashutosh Bapat <
ashutosh.ba...@enterprisedb.com> wrote:
> On Sat, Mar 4, 2017 at 2:50 PM, Robert Haas wrote:
> > On Thu, Mar 2, 2017 at 6:48 PM, Ashutosh Bapat
> > wrote:
> >> On Thu, Mar 2, 2017 at 6:06 PM, Rushabh
On Sat, Mar 4, 2017 at 2:50 PM, Robert Haas wrote:
> On Thu, Mar 2, 2017 at 6:48 PM, Ashutosh Bapat
> wrote:
>> On Thu, Mar 2, 2017 at 6:06 PM, Rushabh Lathia
>> wrote:
>>> While reading through the cost_agg() I found that startup cost for the
>>> group aggregate is not correctly assigned. Due
On Thu, Mar 2, 2017 at 6:48 PM, Ashutosh Bapat
wrote:
> On Thu, Mar 2, 2017 at 6:06 PM, Rushabh Lathia
> wrote:
>> While reading through the cost_agg() I found that startup cost for the
>> group aggregate is not correctly assigned. Due to this explain plan is
>> not printing the correct startup
On Thu, Mar 2, 2017 at 6:48 PM, Ashutosh Bapat
wrote:
> On Thu, Mar 2, 2017 at 6:06 PM, Rushabh Lathia
> wrote:
>> Hi,
>>
>> While reading through the cost_agg() I found that startup cost for the
>> group aggregate is not correctly assigned. Due to this explain plan is
>> not printing the correc
On Thu, Mar 2, 2017 at 6:06 PM, Rushabh Lathia wrote:
> Hi,
>
> While reading through the cost_agg() I found that startup cost for the
> group aggregate is not correctly assigned. Due to this explain plan is
> not printing the correct startup cost.
>
> Without patch:
>
> postgres=# explain select
