Re: MVCC and all that...

> > In part 1. Differences in MVCC implementation - he's saying that "It’s
> > not that the PostgreSQL implementation of MVCC is bad — it’s just
> > fundamentally different"

> It is written by someone @firebirdsql.org so one assumes a few grains of salt necessary.


I know - but the guy does stress that he's not knocking PostgreSQL,
just that there are differences.

However, it *_was_* my understanding that MVCC was implemented
similarly in PostgreSQL and Firebird - PG has VACUUM and FB has SWEEP.
Why would FB need SWEEP if it didn't have to clear up after
transactions - a problem that apparently doesn't affect Oracle/MySQL?

Oracle and MySQL (InnoDB) implement a different model (as does
Orioledb IIUC) where there's are UNDO/REDO logs.

So, my question is: Is FB's MVCC implementation fundamentally
different from that of PG or have I mixed things up?

Thanks for your input.

--

El!