Re: path toward faster partition pruning

On 31 October 2017 at 21:43, Amit Langote <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> wrote:
> Attached updated version of the patches

match_clauses_to_partkey() needs to allow for the way quals on Bool
columns are represented.

create table pt (a bool not null) partition by list (a);
create table pt_true partition of pt for values in('t');
create table pt_false partition of pt for values in('f');
explain select * from pt where a = true;
QUERY PLAN
------------------------------------------------------------------
Append (cost=0.00..76.20 rows=2810 width=1)
-> Seq Scan on pt_false (cost=0.00..38.10 rows=1405 width=1)
Filter: a
-> Seq Scan on pt_true (cost=0.00..38.10 rows=1405 width=1)
Filter: a
(5 rows)

match_clause_to_indexcol() shows an example of how to handle this.

explain select * from pt where a = false;

will need to be allowed too. This works slightly differently.

--
David Rowley http://www.2ndQuadrant.com/
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