Hi all;
I case people on this list have not seen the slashdot discussion
(http://developers.slashdot.org/article.pl?sid=05/11/23/0228258&tid=221&tid=218),
it appears that MySQL has announced a commitment to provide a
replacement to InnoDB to their customers. I wanted to just fill in a
few gaps that came up during my research.
First BDB is not a viable replacement for InnoDB for two reasons both of
which stem from BDB architectural considerations (it simply wasn't
designed to function well as a backend for a high concurrency RDBMS).
Basically, while InnoDB uses MVCC, BDB uses page locks. BDB therefore
has locking issues because you don't have the snapshot capabilities that
MVCC gets you with InnoDB, and it is unlikely that one will ever be able
to provide multiple transaction levels with the BDB storage engine.
MaxDB/SAPDB might be a possibility but I don't know anything about how
it handles things behind the scenes. My uninformed guess is that it
would be no better than BDB, possibly worse.
So my conclusion is that MySQL is biting off quite a bit with this
commitment. One really does not know how long it would take them to
create such a table architecture froms scratch or indeed whether they
are able to if they try.
Best Wishes,
Chris Travers
Metatron Technology Consulting