Re: log bind parameter values on error

Hi Peter,

> With your patch, with log_statement=all and log_parameters=on, you get
> the same, but with log_statement=all and log_parameters=off you get
>
> LOG:  execute <unnamed>: SELECT abalance FROM pgbench_accounts WHERE aid
> = $1;
> DETAIL:  parameters: $1 = UNKNOWN TYPE
Thanks for spotting this, I've fixed it, see the new patch attached.
> This also raises the question of the new parameter name.  Parameters are
> already logged.  So the name should perhaps be more like
> log_parameters_on_error.
Done
> Some API notes on your patch:  I think you can change
> get_portal_bind_parameters() to take a ParamListInfo, since you're not
> doing anything with the Portal other than grab the parameters.  And that
> would allow you to keep the signature of errdetail_params() unchanged.
Done
> I did some performance tests using the commands shown above and didn't
> find any problems.  Obviously the default pgbench stuff isn't very
> parameter-intensive.  Do you have tests with more and larger parameter
> values?
>

I've done some tests, but they are not very reproducible:
the difference between runs is more than the difference between master 
vs feature branch
and log_parameters_on_error on vs off.

I was using a small java app, it tested the speed using only a single 
connection.
See its code and the results attached.

I'm sorry for the delay, feel free to move it to next commitfest if needed.

Best,
   Alex