HashAgg's batching counter starts at 0, but Hash's starts at 1.

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HashAgg's batching counter starts at 0, but Hash's starts at 1.

David Rowley
Hi,

While working on 40efbf870 I noticed that when performing a Hash Join
that we always start out by setting nbatch to 1.  That seems
reasonable as it's hard to imagine being able to complete any non-zero
amount of work in fewer than 1 batch.

In the HashAgg case, since 40efbf870, we'll display:

"HashAgg Batches": 0,

if you do something like: explain(analyze, format json) select
distinct oid from pg_class;

I'd rather this said that the number of batches was 1.

Does anyone have any objections to that being changed?

David


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Re: HashAgg's batching counter starts at 0, but Hash's starts at 1.

Jeff Davis-8
On Tue, Jun 30, 2020, 7:04 PM David Rowley <[hidden email]> wrote:
Does anyone have any objections to that being changed?

That's OK with me. By the way, I'm on vacation and will catch up on these HashAgg threads next week.

Regards,
     Jeff Davis