Re: [HACKERS] Runtime Partition Pruning - Mailing list pgsql-hackers

From David Rowley
Subject Re: [HACKERS] Runtime Partition Pruning
Date
Msg-id CAKJS1f-uv90VELKx34ov-d17sQ1vJg5jUvj19K2xa86f6eieKA@mail.gmail.com
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In response to Re: [HACKERS] Runtime Partition Pruning  (Beena Emerson <memissemerson@gmail.com>)
Responses Re: [HACKERS] Runtime Partition Pruning
List pgsql-hackers
On 22 December 2017 at 01:43, Beena Emerson <memissemerson@gmail.com> wrote:
>> I wonder if Robert understands the extent of the problem. The patch
>> will be useful to prune away partitions when the partitioned table is
>> on the inside of a parameterised nested loop join, but I think we'll
>> likely get some complaints about PREPARE statements always using a
>> custom plan.  It's going to make this pretty hard to write regression
>> tests for unless we went and invent some GUC "prefer_generic_plan", or
>> "generic_plan_cost_multiplier" to provide a way to coax
>> choose_custom_plan() into not choosing a custom plan.  I admit to not
>> having the answer to this but I don't think we should rule out
>> discussing possible fixes.
>
> I have attached the regression tests I am currently using to check my
> patch.  It has few prepared statements using runtime pruning.

Thanks for sending.  Will the tests still pass if you remove the hack
from choose_custom_plan()?


-- 
 David Rowley                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services


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