Re: Optimization for updating foreign tables in Postgres FDW

On Mon, Aug 25, 2014 at 8:58 AM, Albe Laurenz <laurenz.albe@wien.gv.at> wrote:
> Reading the code, I noticed that the pushed down UPDATE or DELETE statement is executed
> during postgresBeginForeignScan rather than during postgresIterateForeignScan.
> It probably does not matter, but is there a reason to do it different from the normal scan?

Hmm, I'm worried that may be an API contract violation.  ISTM that we
might initialize nodes that we never read from - they can show up in
the EXPLAIN-plan as (never executed) - and things that aren't executed
shouldn't do work, especially work that permanently modifies data.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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