Re: syntax of joins

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От Pavel Stehule
Тема Re: syntax of joins
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Msg-id CAFj8pRAeQO6cJRTWQdp+LsTS8aK+LpQwRLP1cv5PPc=Fsh+VSw@mail.gmail.com
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Ответ на Re: syntax of joins  (Rob Sargent <robjsargent@gmail.com>)
Ответы Re: syntax of joins  (Rob Sargent <robjsargent@gmail.com>)
Список pgsql-sql
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
>>
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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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