Re: Regarding ambulkdelete, amvacuumcleanup index methods

Thanks for your response.

Hope those stats will be used by Query Planner.

So, just for my understanding, if i don't return stats (returning NULL from
index_bulk_delete and index_vacuum_cleanup functions), Query Planner will
not consider my Index as part of Query Path, beyond that i don't expect any
bad consequences.

Please clarify me, if i'm wrong.

Regards,
Abinaya K

> On Wed, Jan 24, 2018 at 1:24 PM, Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>
> wrote:
>
>> On Wed, Jan 24, 2018 at 1:27 PM, Abinaya k <abinaya(dot)k(dot)496(at)gmail(dot)com>
>> wrote:
>> > Hai all,
>> > We are building In-memory index extension for postgres. We would
>> > capture table inserts, updates, deletes using triggers. During vacuum
>> > operation, postgres would give calls to ambulkdelete, amvacuumcleanup
>> (as
>> > part of index cleanup). As we handle all updates, deletes using
>> triggers, we
>> > don't have to do any index cleanup in ambulkdelete. But, what stats
>> should i
>> > return from ambulkdelete and amvacuumcleanup? Is that necessary to
>> return
>> > stats from ambulkdelete and amvacuumcleanup ?
>>
>> Both ambulkdelete and amvacuumcleanup return an IndexBulkDeleteResult.
>> If you return a non-NULL value, the values of returned
>> IndexBulkDeleteResult are used for updating the index statistics and
>> reporting the statistics of bulk deletion in lazy_cleanup_index. For
>> example, num_pages and num_index_tuples are used for updating
>> pg_class.relpages and pg_class.reltuples. But if you return NULL from
>> them, these are skipped.
>>
>> Regards,
>>
>> --
>> Masahiko Sawada
>> NIPPON TELEGRAPH AND TELEPHONE CORPORATION
>> NTT Open Source Software Center
>>
>
>