From: Paul Lambert <plengada@optusnet.com.au>
To: Ken Johanson <pg-user@kensystem.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Shorthand column labels (SELECT col1 foo, ...) vs (SELECT col1 AS foo, ...)
Date: Thu, 10 Jan 2008 17:04:04 +0900
Message-ID: <4785D174.4030203@optusnet.com.au> (raw)
In-Reply-To: <4785CBE9.6000108@kensystem.com>
References: <4785C50F.6010505@kensystem.com>
<4785C744.6080406@optusnet.com.au>
<4785CBE9.6000108@kensystem.com>
Ken Johanson wrote:
> Interesting thread(s)!
>
> What I didn't see discussed was the possibility of making a server
> and/or session option, where we could elect to turn-off the old behavior
> (PG specific behavior) and enable the standard/shorthand syntax. Users
> need a migration path.
>
> I personally cant ever see using those PGisms/features and would choose
> to enable the standard mode. I think I'd have fewer compatibility problems.
>
> Ken
What was discussed is that the AS keyword is required because of the way
the interpreter parses the commands.
With the example given, how does it know that 1::character varying isn't
casting to a character field with an alias of varying or a character
varying field with no alias?
If there was simply a switch to turn the requirement on or off that's
not going to stop things from breaking - the postfix operators still
need to be picked up somehow, it's a technical limitation rather than a
"let's just be difficult and be incompatible with other dbms's" limitation
I think it would be nice as well, I had to migrate a system that didn't
bother putting AS in any of it's views/stored procedures etc and went
through this pain - but I think having to change everything was worth it
to make sure all my scripts were correctly written and free from
possible misinterpretation.
My thoughts anyway.
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To: pgsql-sql@postgresql.org
Cc: plengada@optusnet.com.au, pg-user@kensystem.com
Subject: Re: Shorthand column labels (SELECT col1 foo, ...) vs (SELECT col1 AS foo, ...)
In-Reply-To: <4785D174.4030203@optusnet.com.au>
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