Re: Default setting for enable_hashagg_disk

On 2020-Jul-27, Peter Geoghegan wrote:

> The v4-0001-Remove-hashagg_avoid_disk_plan-GUC.patch changes are
> surprisingly complicated. It would be nice if you could take a look at
> that aspect (or confirm that it's included in your review).

I think you mean "it replaces surprisingly complicated code with
straightforward code".  Right?  Because in the previous code, there was
a lot of effort going into deciding whether the path needed to be
generated; the new code just generates the path always.

Similarly the code to decide allow_hash in create_distinct_path, which
used to be nontrivial, could (if you wanted) be simplified down to a
single boolean condition.  Previously, it was nontrivial only because
it needed to consider memory usage -- not anymore.

But maybe you're talking about something more subtle that I'm just too
blind to see.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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