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nic
I've been using the old style forever (with comma delimited tables and condition in the where clause), but I just read in a book that the new style ( with the words JOIN) might perform better
Is that true?
The book wasn't exclusively on Oracle; it was about RDBMS in general.
Could it be true only in SQL server or other RDBMS?

Thanks
dave
perform the same, the ANSI join syntax is the 'correct way' though
burleson
Hi Nic,

>> I just read in a book that the new style ( with the words JOIN) might perform better

I've never heard that one!

What book? Can you tell us exactly what it says, please?

Of course, you need to look under the covers with explain plan to see:

http://www.dba-oracle.com/t_sql_execution_plan_tips.htm

But the choice for joins is usually "nested loop" vs. "Hash". See here for details:

http://www.dba-oracle.com/tips_oracle_sql_...nested_hash.htm

************************************************************************
>> Could it be true only in SQL server or other RDBMS?

Sure!

A database is just a large set of computer programs (Oracle is written in C).

You can make it do whatever you want!
nic
Thank you both for your quick responses
That is what I thought too.
I believe the rule is applicable to sql server, but not to oracle
Considering that oracle didn't even support the ansi standard in the previous versions, it doesn't really make any sense to make it faster

Database performance is something that is been bugging me in the last couple of months and I am looking for every possible way to make a query faster. That is how I started reading all kind of performace tuning books. I guess, some of them just confuse me more that help me
thanks
nic
burleson
Hi Nic,

Do you recall what book has that notes on different performance of different joins?

>> That is how I started reading all kind of performace tuning books.

That's good! Many folks have very different approaches, but they all work!

>> I am looking for every possible way to make a query faster.

Well, that's what I do for a living, if you want to post it here (with the explain plan). . .
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