David Johnson wrote:

>
> Is a two-phase commit necessary (Conversely, does it matter if you lose
> data under some circumstances)? MySQL, for example, does not support
> two phase commit, whereas Firebird does. This gives MySQL a performance
> edge in the benchmarks, but results in data loss in some circumstances.

Errm, do you know the cost of two-phase commit in Firebird? It's
approximately nothing - one extra record written in each participating
database when a read/write transaction enters the prepare phase, which
happens only for multi-database transactions. There's probably some
benchmark that can find it. The absence of a two-phase commit doesn't
"lose data" - but in inconsistent transaction results in multi-database
applications.

A problem with benchmarking against MySQL is knowing which backend
you're comparing with - some don't have transactions at all. That
backend does get some speed advantages from not having to carry any
ability to undo groups of actions, but, one might argue, it isn't really
a database.


Regards,


Ann