Re: [HACKERS] pgbench - allow to store select results intovariables - Mailing list pgsql-hackers

From Fabien COELHO
Subject Re: [HACKERS] pgbench - allow to store select results intovariables
Date
Msg-id alpine.DEB.2.21.1811180851210.19159@lancre
Whole thread Raw
In response to Re: [HACKERS] pgbench - allow to store select results into variables  (Alvaro Herrera <alvherre@2ndquadrant.com>)
Responses Re: [HACKERS] pgbench - allow to store select results into variables
List pgsql-hackers
Hello Alvaro,

>>> I think this patch's Command->lines would benefit from using PQExpBuffer
>>> (or maybe StringInfo?) for the command string instead of open-coding
>>> string manipulation and allocation.
>
> [...]

Ok.

>>> I'm not sure that Command->first_line is really all that useful.  It
>>> seems we go to a lot of trouble to keep it up to date.  Isn't it easier
>>> to chop Command->lines at the first newline when it is needed?
>>
>> Hmmm, it is needed quite often (about 12 times) to report errors, that would
>> mean having to handle the truncation in many places, so I felt it was worth
>> the trouble.
>
> Ok, as long as we don't repeat the work during script execution.

Sure, the point of first_line is that it is computed once at parse time.

Attached a v23 with PQExpBuffer for managing lines.

I've also added a function to compute the summary first line, which 
handles carriage-return.

-- 
Fabien.
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