On Mon, Nov 11, 2013 at 07:25:59PM -0800, David Johnston wrote:
> This reads badly to my ears:
>
>
> > This means that while querying a database each SQL statement sees a
> > snapshot of data (a database version) as it was some time ago, regardless
> > of the current state of the underlying data.
Bruce Momjian wrote
> We just want to get across the MVCC concept in the intro --- we cover
> the snapshots later in the document.
I just think we're being too vague here; and we are covering them in the
intro with the use of "some point in the past".
IMO, the main point regarding MVCC is that ev
On Tue, Nov 12, 2013 at 03:36:01PM -0800, David Johnston wrote:
> Bruce Momjian wrote
> > We just want to get across the MVCC concept in the intro --- we cover
> > the snapshots later in the document.
>
> I just think we're being too vague here; and we are covering them in the
> intro with the use
Bruce Momjian wrote
> On Tue, Nov 12, 2013 at 03:36:01PM -0800, David Johnston wrote:
>> Bruce Momjian wrote
>> > We just want to get across the MVCC concept in the intro --- we cover
>> > the snapshots later in the document.
>>
>> I just think we're being too vague here; and we are covering them
On Tue, Nov 12, 2013 at 05:35:23PM -0800, David Johnston wrote:
> Bruce Momjian wrote
> > On Tue, Nov 12, 2013 at 03:36:01PM -0800, David Johnston wrote:
> >> Bruce Momjian wrote
> >> > We just want to get across the MVCC concept in the intro --- we cover
> >> > the snapshots later in the document.
Bruce Momjian wrote
> Oh, OK, it sounds fine. The user really doesn't choose what timeline to
> see --- rather, it is the current xid at the time they take their
> snapshot and other running xids that controls that. You can control
> your transaction isolation level, but that only controls how of
