Re: Clarify log_parameter_max_length docs regarding log_min_duration_statement vs log_duration - Mailing list pgsql-docs

From surya poondla
Subject Re: Clarify log_parameter_max_length docs regarding log_min_duration_statement vs log_duration
Date
Msg-id CAOVWO5onzDm4oBx+VSdHZM+_nhiHi07rS9M72Y=9-DTUkmCs3A@mail.gmail.com
Whole thread
In response to Clarify log_parameter_max_length docs regarding log_min_duration_statement vs log_duration  (Fujii Masao <masao.fujii@gmail.com>)
Responses Re: Clarify log_parameter_max_length docs regarding log_min_duration_statement vs log_duration
List pgsql-docs
 Hi Fujii,

The current wording in the docs is misleading. +1 to the patch for correcting it.
log_parameter_max_length only affects the "Parameters: ..." line that appears alongside logged statements in the server log.  
That line is never emitted when only log_duration is turned on. It only shows up when log_min_duration_statement (or a sample-rate variant) is what causes the statement to be logged.
So the change looks accurate.

(Pointer for anyone tracing it: log_parameter_max_length is read only inside errdetail_params(), and the log_duration-
only path through check_log_duration() the return-1 arm never routes through it.)

Two small questions:

1. log_min_duration_sample and log_transaction_sample_rate also cause "Parameters:" lines to be emitted, and are therefore
also affected by log_parameter_max_length.  "and related settings" arguably covers them, but if we want the enumeration to be more
precise than before, would it be worth naming them explicitly? Either way is fine just curious about the rationale.

2. This wording was introduced in 0b34e7d307e and is in every supported branch. Should this be back patched?

Regards,
Surya Poondla

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