"As you probably already know, MySQL supports a number of
different storage engines. This powerful architecture allows MySQL
to take advantage of the transactional power of InnoDB tables when
you need that, and the lightening speed of MyISAM tables, when you
don't need row-level locking and ACID compliance.
"When it comes to replication, however, it can pose challenges.
The binary log won't receive transactions that either fail, or
otherwise rollback via a user request. That's good, so they won't
be sent down the pike to the slave database; but what if you have a
mixed query with MyISAM and InnoDB tables? Well it turns out that
the transaction in that session will replicate fine. However if
there are additional concurrent sessions updating that MyISAM table
before that transaction completes, then those statements will get
logged out of order."