Brian, Jeff,
> > I have never understood the purpose of having more than one "backend" to
> > the database. As near as I can figure, it's only purpose is to allow
> > people to pick the wrong one.
Well, the real purpose of the backend storage engines is to make MySQL into
more than one kind of database. MyISAM is for a single-user DB, InnoDB is
for transactions, NDB is clustered & object, Ericsson is telecom, MemDB is
in-memory, etc. It makes up for the fact that MySQL does not excel in any
one database category if it is percieved to be adequate in all categories.
> In MySQL, changing the "storage engine" can break user queries and
> always requires a full data migration to the new format.
Sure, but MySQL users and potential users don't perceive it that way -- they
encounter the problems only long after they've made hard-to-revoke decisions
to adopt MySQL. MySQL is still much, much better at marketing than we are.
--
Josh Berkus
PostgreSQL @ Sun
San Francisco