Re: Speed dblink using alternate libpq tuple storage - Mailing list pgsql-hackers

From Kyotaro HORIGUCHI
Subject Re: Speed dblink using alternate libpq tuple storage
Date
Msg-id CAM103DtrZUskPo7Au3PDsSer7SQ2F8VGx=0DgQfFUdSzo5ckew@mail.gmail.com
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In response to Re: Speed dblink using alternate libpq tuple storage  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Speed dblink using alternate libpq tuple storage  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: Speed dblink using alternate libpq tuple storage  (Kyotaro HORIGUCHI <horiguchi.kyotaro@oss.ntt.co.jp>)
List pgsql-hackers
Hello, This is the new version of dblink patch.

- Calling dblink_is_busy prevents row processor from being used.

- some PGresult leak fixed.

- Rebased to current head.

> A hack on top of that hack would be to collect the data into a
> tuplestore that contains all text columns, and then convert to the
> correct rowtype during dblink_get_result, but that seems rather ugly
> and not terribly high-performance.
>
> What I'm currently thinking we should do is just use the old method
> for async queries, and only optimize the synchronous case.

Ok, I agree with you except for performance issue. I give up to use
row processor for async query with dblink_is_busy called.

> I thought for awhile that this might represent a generic deficiency
> in the whole concept of a row processor, but probably it's mostly
> down to dblink's rather bizarre API.  It would be unusual I think for
> people to want a row processor that couldn't know what to do until
> after the entire query result is received.

I hope so. Thank you.

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center

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