Re: Resetting spilled txn statistics in pg_stat_replication

(Please avoid top-posting)

On Mon, 12 Oct 2020 at 23:45, Shinoda, Noriyoshi (PN Japan A&PS
Delivery) <noriyoshi.shinoda@hpe.com> wrote:
>
> Sawada-san, Thank you your comments.
>
> The attached patch reflects the comment.
> I also made a fix for the regression test.
>
> Regards,
> Noriyoshi Shinoda
>
> -----Original Message-----
> From: Masahiko Sawada [mailto:masahiko.sawada@2ndquadrant.com]
> Sent: Monday, October 12, 2020 8:12 PM
> To: Shinoda, Noriyoshi (PN Japan A&PS Delivery) <noriyoshi.shinoda@hpe.com>
> Cc: Amit Kapila <amit.kapila16@gmail.com>; Dilip Kumar <dilipbalaut@gmail.com>; Magnus Hagander
<magnus@hagander.net>;Tomas Vondra <tomas.vondra@2ndquadrant.com>; PostgreSQL Hackers
<pgsql-hackers@lists.postgresql.org>;Ajin Cherian <itsajin@gmail.com> 
> Subject: Re: Resetting spilled txn statistics in pg_stat_replication
>
> On Mon, 12 Oct 2020 at 18:29, Shinoda, Noriyoshi (PN Japan A&PS
> Delivery) <noriyoshi.shinoda@hpe.com> wrote:
> >
> > Hi, thank you for the awesome feature.
> >
>
> Thank you for reporting!
>
> > As it may have been discussed, I think the 'name' column in pg_stat_replication_slots is more consistent with the
columnname and data type matched to the pg_replication_slots catalog. 
> > The attached patch changes the name and data type of the 'name' column to slot_name and 'name' type, respectively.
>
> It seems a good idea to me. In other system views, we use the name data type for object name. When I wrote the first
patch,I borrowed the code for pg_stat_slru which uses text data for the name but I think it's an oversight. 

Hmm, my above observation is wrong. All other statistics use text data
type and internally use char[NAMEDATALEN]. So I think renaming to
'slot_name' would be a good idea but probably we don’t need to change
the internally used data type. For the data type of slot_name of
pg_stat_replication_slots view, given that the doc says the
following[1], I think we can keep it too as this view is not a system
catalog. What do you think?

8.3. Character Types:
The name type exists only for the storage of identifiers in the
internal system catalogs

[1] https://www.postgresql.org/docs/devel/datatype-character.html

Regards,

--
Masahiko Sawada            http://www.2ndQuadrant.com/
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