Re: [HACKERS] Partition-wise join for join between (declaratively)partitioned tables - Mailing list pgsql-hackers

From Ashutosh Bapat
Subject Re: [HACKERS] Partition-wise join for join between (declaratively)partitioned tables
Date
Msg-id CAFjFpRd0wuFZA=sEckMS2etTk9zTweBNg4TS8VdgCK6KKN5erw@mail.gmail.com
Whole thread Raw
In response to Re: [HACKERS] Partition-wise join for join between (declaratively)partitioned tables  (Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>)
List pgsql-hackers
On Tue, Mar 14, 2017 at 6:28 AM, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> On 2017/03/14 9:17, Robert Haas wrote:
>> On Mon, Mar 13, 2017 at 3:24 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>>> Haven't looked at 0007 yet.
>>
>> Overall this one looks pretty good and straightforward.
>
> In the following code of find_partition_scheme():
>
> +       /* Did not find matching partition scheme. Create one. */
> +       part_scheme = (PartitionScheme) palloc0(sizeof(PartitionSchemeData));
> +
> +       /* Copy partition bounds/lists. */
> +       part_scheme->nparts = part_desc->nparts;
> +       part_scheme->strategy = part_key->strategy;
> +       part_scheme->boundinfo = part_desc->boundinfo;
> +
> +       /* Store partition key information. */
> +       part_scheme->partnatts = part_key->partnatts;
> +
> +       part_scheme->partopfamily = (Oid *) palloc(sizeof(Oid) * partnatts);
> +       memcpy(part_scheme->partopfamily, part_key->partopfamily,
> +                  sizeof(Oid) * partnatts);
> +
> +       part_scheme->partopcintype = (Oid *) palloc(sizeof(Oid) * partnatts);
> +       memcpy(part_scheme->partopcintype, part_key->partopcintype,
> +                  sizeof(Oid) * partnatts);
> +
> +       part_scheme->key_types = (Oid *) palloc(sizeof(Oid) * partnatts);
> +       memcpy(part_scheme->key_types, part_key->parttypid,
> +                  sizeof(Oid) * partnatts);
> +
> +       part_scheme->key_typmods = (int32 *) palloc(sizeof(int32) * partnatts);
> +       memcpy(part_scheme->key_typmods, part_key->parttypmod,
> +                  sizeof(int32) * partnatts);
> +
> +       part_scheme->key_collations = (Oid *) palloc(sizeof(Oid) * partnatts);
> +       memcpy(part_scheme->key_collations, part_key->parttypcoll,
> +                  sizeof(Oid) * partnatts);
>
> Couldn't we avoid the memcpy() on individual members of part_key?  After
> all, RelationData.rd_partkey is guarded just like rd_partdesc by
> relcache.c in face of invalidations (see keep_partkey logic in
> RelationClearRelation).

This suggestion looks good to me. Incorporated in the latest set of patches.


-- 
Best Wishes,
Ashutosh Bapat
EnterpriseDB Corporation
The Postgres Database Company



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