Re: REFRESH MATERIALIZED VIEW and completion tag output

> On Nov 5, 2020, at 4:45 PM, Fujii Masao <masao(dot)fujii(at)oss(dot)nttdata(dot)com> wrote:
>
>
>
> On 2020/11/06 1:56, Mark Dilger wrote:
>>> On Nov 5, 2020, at 8:20 AM, Fujii Masao <masao(dot)fujii(at)oss(dot)nttdata(dot)com> wrote:
>>>
>>> The patch that makes pg_stat_statements track the number of rows that
>>> REFRESH MATERIALIZED VIEW command processes was proposed at [1].
>>> When reviewing the patch, I just wondered why the completion tag output
>>> for REFRESH MATERIALIZED VIEW doesn't include the row count. Is this
>>> an intentional behavior? I've not found the past discussion about this yet.
>> Of 191 command tags, only 7 return the number of rows. See src/include/tcop/cmdtaglist.h. REFRESH MATERIALIZED VIEW is similar to CREATE MATERIALIZED VIEW and also CREATE TABLE AS, which also do not return the row count.
>
> Yes, so I was wondering if REFRESH MATERIALIZED VIEW also should use
> CMDTAG_SELECT like CREATE MATERIALIZED VIEW does.

For both CREATE MATERIALIZED VIEW and CREATE TABLE AS, ExecCreateTableAs() does:

SetQueryCompletion(qc, CMDTAG_SELECT, queryDesc->estate->es_processed);

but ExecRefreshMatView() does nothing with it's QueryCompletion parameter. I don't know why this case should behave differently than the other two.

—
Mark Dilger
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