Re: Performance Optimization for Dummies 2 - the SQL

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От Jim C. Nasby
Тема Re: Performance Optimization for Dummies 2 - the SQL
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Msg-id 20061008203450.GK72517@nasby.net
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Ответ на Re: Performance Optimization for Dummies 2 - the SQL  ("Merlin Moncure" <mmoncure@gmail.com>)
Ответы Re: Performance Optimization for Dummies 2 - the SQL  ("Merlin Moncure" <mmoncure@gmail.com>)
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On Thu, Oct 05, 2006 at 09:30:45AM -0400, Merlin Moncure wrote:
> I personally only use explicit joins when doing outer joins and even
> them push them out as far as possible.

I used to be like that too, until I actually started using join syntax.
I now find it's *way* easier to identify what the join conditions are,
and to seperate them from the rest of the where clause. It also makes it
pretty much impossible to mess up a join clause and get a cartesian
product.

If you are going to put the join clauses in the WHERE clause, at least
put a space between the join stuff and the rest of the WHERE clause.

In any case, this is nothing but a matter of taste in this case, unless
you set join_collapse_limit to less than 3 (or maybe 4).
--
Jim Nasby                                            jim@nasby.net
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)

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