On Tue, Jun 13, 2017 at 10:05 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> Perhaps this is a silly question, but I don't particularly see what's
>> wrong with:
>
>> 3. Do nothing.
>
> Well, the fundamental problem is that the RTE is a lousy place to keep
> rowcount estimates. That breaks assorted desirable properties like
> querytrees being readonly to planning/execution (not that we don't
> end up copying them anyway, but up to now that's been because of bad
> implementation not because the representation was broken by design).
How does it break those properties? I don't think enrtuples is being
modified by planning or execution as things stand.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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