Re: syntax of joins

From: Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
To: Rob Sargent <robjsargent(at)gmail(dot)com>
Cc: pgsql-sql(at)postgresql(dot)org
Subject: Re: syntax of joins
Date: 2012-04-06 19:46:40
Message-ID: CAFj8pRAeQO6cJRTWQdp+LsTS8aK+LpQwRLP1cv5PPc=Fsh+VSw@mail.gmail.com
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2012/4/6 Rob Sargent <robjsargent(at)gmail(dot)com>:
> On 04/06/2012 01:23 PM, Pavel Stehule wrote:
>>
>> Hello
>>
>> 2012/4/6 Andreas<maps(dot)on(at)gmx(dot)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
>>
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>>
>>
> In other words, no disadvantage :)
>

Hard to say - for man who fixed critical cartesian products :) in queries

Pavel

> -some cranky old guy who still misses "retrieve"
>
>
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