> and ore people are joining tables using the...
>
> FROM table1 x JOIN table2 y ON x.ID = y.ID
>
> And I am wondering if there is a reason for this. Sure I use
> this syntax for my outer joins but inner joins I still do the
> old fashioned way in the where clause, for example
>
> FROM table1 x, table2 y
> WHERE x.ID = y.ID
>
> This has the added benefit of taking the place of the 'WHERE
> 0=0' line we recently discussed. What are the benefits of
> one form of inner join over the other or is it just today's
> SQL fashion trend?
It's hardly a fashion trend - it's the law (ANSI SQL 92 specification). Most
modern databases support explicit JOINs.
It provides two benefits. Jochem mentioned that it separates filters from
join conditions. As a byproduct of this, it prevents unintentional Cartesian
products or cross joins, which can easily happen when you perform joins in a
WHERE clause.
Dave Watts, CTO, Fig Leaf Software
http://www.figleaf.com/
phone: 202-797-5496
fax: 202-797-5444
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