Date: Wed, 27 Jan 2016 00:17:55 +0100
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Fabien COELHO <coelho@cri.ensmp.fr>
Cc: "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: pgbench stats per script & other stuff
Message-ID: <20160126231755.GA580522@alvherre.pgsql>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <alpine.DEB.2.10.1601231501570.21060@sto>
User-Agent: Mutt/1.5.23 (2014-03-12)
Precedence: bulk
Sender: pgsql-hackers-owner@postgresql.org

Fabien COELHO wrote:

> a) add -b option for cumulating builtins and rework internal script
>    management so that builtin and external scripts are managed the
>    same way.

I'm uncomfortable with the prefix-matching aspect of -b.  It makes
"-b s" ambiguous -- whether it stands for select-only or simple-update
is merely a matter of what comes earlier in the table, which doesn't
seem reasonable to me.  I'd rather have a real way to reject ambiguous
cases, or simply accept only complete spellings.  This is the guilty
party:

> +static char *
> +find_builtin(const char *name, char **desc)
> +{
> +	int		len = strlen(name), i;
> +
> +	for (i = 0; i < N_BUILTIN; i++)
> +	{
> +		if (strncmp(builtin_script[i].name, name, len) == 0)
> +		{
> +			*desc = builtin_script[i].desc;
> +			return builtin_script[i].script;
> +		}
> +	}

I'm going to change this to use strlen(builtin_script[i].name) instead
of "len" here.

If you want to implement real non-ambiguous-prefix code (i.e. have "se"
for "select-only", but reject "s" as ambiguous) be my guest.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


-- 
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers