Re: MVCC and all that...

> Note: your link is wrong, corrected here:

Extra hyphen - sorry about and thanks for pointing it out!

> What the article is driving at is that postgres does not use rollback logs to handle updated records in the MVCC implementation. There are absolutely performance tradeoffs in that decision and, if you do a lot of development against postgresql, those tradeoffs should influence how you design databases. The author then cherry picked the 'worst case' case, large unconstrained updates.

Hmm... I was wondering about that - even though he stressed that there
was (paraphrasing) no right or wrong - just different design
decisions!

> The article is a bit of a cheezy dig on postgres. Another example is the complaint about autonomous transactions with another cherry picked example to make postgres look back. In the real world, these would not matter much, and can be worked around (if you want to see my take on how to deal with it, see here: https://github.com/leaselock/pgasync)

OK - so, I was wrong in my original assumption that somehow (and it
wasn't simply because of the phraseology - sweep vs vacuum) I thought
that PG and FB had a similar MVCC implementation vs. Oracle and MySQL
(InnoDB) (and OrioleDB). I'll do a deep dive into their docco and see
what they actually do! I'm actually very interested in the
benchmarking side of database technology - but I do know the old adage
- there are lies, damned lies, statistics and *_then_* there are
database benchmarks (as seen with the link I posted!).

Thanks for your input.

Best regards,

El!

> merlin