Re: syntax of joins - Mailing list pgsql-sql

From Pavel Stehule
Subject Re: syntax of joins
Date
Msg-id CAFj8pRBc2Qa+_Zap_8VqOQzjaYWXtkajjhKePKs9pYGnkcoX+w@mail.gmail.com
Whole thread Raw
In response to syntax of joins  (Andreas <maps.on@gmx.net>)
Responses Re: syntax of joins  (Rob Sargent <robjsargent@gmail.com>)
List pgsql-sql
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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