Re: ACID et al

paul c wrote:
> vc wrote:
> > paul c wrote:
> >
> >>vc wrote:
> >>
> >>>paul c wrote:
> >>>
> >>>
> >>>>I'm interested to see any comments the group has on something I'm
> >>>>(haphazardly) working on which in part has to do with guaranteeing the
> >>>>ACID properties without locking.
> >>>
> >>>
> >>>Locking (or any other concurrency mechanism) is relevant only to, well,
> >>>concurrent transactions.
> >>
> >>Yes, another way to say what I meant might be that such an implemention
> >>wouldn't support concurrent transactions, only concurrent users!
> >
> >
> >
> > Well then, it's different matter altogether from saying that you have
> > one-threaded execution only ! You have one read/write transaction and
> > many concurrent read-only transactions, ....
>
> No. No 'transaction' is ever concurrent with another, regardless of
> whether it contains 'reads' and/or 'writes'. I say 'single-threaded'
> only because if I said 'single process', somebody might infer that
> multiple-threads were possible.
>

Ah, ok, so if there is no *concurrent* access to a data item, then there is no need to worry about locking and such. Received on Mon Dec 05 2005 - 20:40:54 CET