From: Rob Sargent <robjsargent@gmail.com>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: syntax of joins
Date: Fri, 06 Apr 2012 14:14:40 -0600
Message-ID: <4F7F4EB0.6050902@gmail.com> (raw)
In-Reply-To: <CAFj8pRAeQO6cJRTWQdp+LsTS8aK+LpQwRLP1cv5PPc=Fsh+VSw@mail.gmail.com>
References: <4F7F3CD9.9090103@gmx.net>
<CAFj8pRBc2Qa+_Zap_8VqOQzjaYWXtkajjhKePKs9pYGnkcoX+w@mail.gmail.com>
<4F7F43C8.4010204@gmail.com>
<CAFj8pRAeQO6cJRTWQdp+LsTS8aK+LpQwRLP1cv5PPc=Fsh+VSw@mail.gmail.com>
On 04/06/2012 01:46 PM, Pavel Stehule wrote:
> 2012/4/6 Rob Sargent<robjsargent@gmail.com>:
>> On 04/06/2012 01:23 PM, Pavel Stehule wrote:
>>>
>>> Hello
>>>
>>> 2012/4/6 Andreas<maps.on@gmx.net>:
>>>>
>>>> hi,
>>>>
>>>> is there a disadvantage to write a join as
>>>>
>>>> select *
>>>> from a, b
>>>> where a.id = b.a_id;
>>>>
>>>
>>>> over
>>>>
>>>> select *
>>>> from a join b on a.id = b.a_id;
>>>>
>>>
>>> yes - newer notation has some advantages
>>>
>>> * clean specification join predicate and filter predicate
>>> * simple adaptability to outer join
>>> * increased protection against copy/paste bug that introduce Cartesian
>>> product
>>>
>>> Regards
>>>
>>> Pavel Stehule
>>>
>>>> --
>>>> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
>>>> To make changes to your subscription:
>>>> http://www.postgresql.org/mailpref/pgsql-sql
>>>
>>>
>> In other words, no disadvantage :)
>>
>
> Hard to say - for man who fixed critical cartesian products :) in queries
>
> Pavel
but doesn't there remain "a join b on a.id != b.id"
(I do use the join syntax -- sometimes, honest)
rjs
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To: pgsql-sql@postgresql.org
Cc: robjsargent@gmail.com, pavel.stehule@gmail.com
Subject: Re: syntax of joins
In-Reply-To: <4F7F4EB0.6050902@gmail.com>
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