Does sql sql efficiency depend on order of join predicate?

hello experts,
I trying to under stand the explain plan , I read the link
http://savvinov.com/2012/06/11/sql-efficiency/
Example 3: The inefficiency is coming from the wrong join order, where the bigger row source is taken as the driving table.
please explain.
thanks
yahs

Hi Nikolay,
What matters is the order in which a join is executed, not the order in which you specify join conditionsHmmm. Not really in all cases.
As jonathan Lewis pointed it out in the following article
http://jonathanlewis.wordpress.com/2010/12/15/join-surprise/#more-5104
With multi-column joins, the order of the join predicates can make a big difference to the way Oracle operates a merge join
Best regards
Mohamed Houri
www.hourim.wordpress.com

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