File content logging during execution of COPY queries (was: Better logging of COPY queries if log_statement='all') - Mailing list pgsql-hackers

From Aleksander Alekseev
Subject File content logging during execution of COPY queries (was: Better logging of COPY queries if log_statement='all')
Date
Msg-id 20161020093652.GB24208@e733.localdomain
Whole thread Raw
In response to Re: [PATCH] Better logging of COPY queries if log_statement='all'  (Aleksander Alekseev <a.alekseev@postgrespro.ru>)
Responses Re: File content logging during execution of COPY queries (was: Better logging of COPY queries if log_statement='all')  (Stephen Frost <sfrost@snowman.net>)
Re: File content logging during execution of COPY queries  (Grigory Smolkin <g.smolkin@postgrespro.ru>)
List pgsql-hackers
> > > According to my colleagues it would be very nice to have this feature.
> > > For instance, if you are trying to optimize PostgreSQL for application
> > > that uses COPY and you don't have access to or something like this.
> > > It could also be useful in some other cases.
> >
> > This use-case doesn't really make much sense to me.  Can you explain it
> > in more detail?  Is the goal here to replicate all of the statements
> > that are changing data in the database?
>
> The idea is to record application workload in real environment and write
> a benchmark based on this record. Then using this benchmark we could try
> different OS/DBMS configuration (or maybe hardware), find an extremum,
> then change configuration in production environment.
>
> It's not always possible to change an application or even database (e.g.
> to use triggers) for this purpose. For instance, if DBMS is provided as
> a service.
>
> Currently PostgreSQL allows to record all workload _except_ COPY
> queries. Considering how easily it could be done I think it's wrong.
> Basically the only real question here is how it should look like in
> postgresql.conf.

OK, how about introducing a new boolean parameter named log_copy?
Corresponding patch is attached.

--
Best regards,
Aleksander Alekseev

Attachment

pgsql-hackers by date:

Previous
From: Etsuro Fujita
Date:
Subject: Re: postgres_fdw : altering foreign table not invalidating prepare statement execution plan.
Next
From: Jeevan Chalke
Date:
Subject: Re: Aggregate Push Down - Performing aggregation on foreign server