Re: Allowing line-continuation in pgbench custom scripts

On 05/26/2014 08:52 AM, Tom Lane wrote:
> Alvaro Herrera <alvherre@2ndquadrant.com> writes:
>> Amit Langote wrote:
>>> On Mon, May 26, 2014 at 10:59 PM, Fujii Masao <masao.fujii@gmail.com> wrote:
>>>> IMO it's better if we can write SQL in multiples line *without* a tailing
>>>> escape character, like psql's input file.
> 
>>> Yeah, that would be much cleaner.
> 
>> But that would require duplicating the lexing stuff to determine where
>> quotes are and where commands end.  There are already some cases where
>> pgbench itself is the bottleneck; adding a lexing step would be more
>> expensive, no?  Whereas simply detecting line continuations would be
>> cheaper.
> 
> Well, we only parse the script file(s) once at run start, and that time
> isn't included in the TPS timing, so I don't think performance is really
> an issue here.  But yeah, the amount of code that would have to be
> duplicated out of psql is pretty daunting --- it'd be a maintenance
> nightmare, for what seems like not a lot of gain.  There would also
> be a compatibility issue if we went this way, because existing scripts
> that haven't bothered with semicolon line terminators would break.

What if we make using semicolons or not a config option in the file?  i.e.:

\multiline




-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com