Le 22/03/2019 à 07:38, Amit Langote a écrit : > Hosoya-san, > > On 2019/03/22 15:02, Yuzuko Hosoya wrote: >> I understood Amit's proposal. But I think the issue Thibaut reported would >> occur regardless of whether clauses have OR clauses or not as follows. >> I tested a query which should output "One-Time Filter: false". >> >> # explain select * from test2_0_20 where id = 25; >> QUERY PLAN >> ----------------------------------------------------------------------- >> Append (cost=0.00..25.91 rows=6 width=36) >> -> Seq Scan on test2_10_20_def (cost=0.00..25.88 rows=6 width=36) >> Filter: (id = 25) >> > Good catch, thanks. > >> As Amit described in the previous email, id = 25 contradicts test2_0_20's >> partition constraint, so I think this clause should be ignored and we can >> also handle this case in the similar way as Amit proposal. >> >> I attached v1-delta-2.patch which fix the above issue. >> >> What do you think about it? > It looks fine to me. You put the code block to check whether a give > clause contradicts the partition constraint in its perfect place. :) > > Maybe we should have two patches as we seem to be improving two things: > > 1. Patch to fix problems with default partition pruning originally > reported by Hosoya-san > > 2. Patch to determine if a given clause contradicts a sub-partitioned > table's partition constraint, fixing problems unearthed by Thibaut's tests > > About the patch that Horiguchi-san proposed upthread, I think it has merit > that it will make partprune.c code easier to reason about, but I think we > should pursue it separately. > > Thanks, > Amit
Hosoya-san, very good idea to run queries directly on tables partitions! I tested your last patch and if I didn't mix up patches on the end of a too long week, I get a problem when querying the sub-sub partition: test=# explain select * from test2_0_10 where id = 25; QUERY PLAN ------------------------------------------------------------ Seq Scan on test2_0_10 (cost=0.00..25.88 rows=6 width=36) Filter: (id = 25) (2 rows) Cordialement, Thibaut
