Re: WIP: System Versioned Temporal Table

On Thu, Oct 24, 2019 at 6:49 PM Vik Fearing <vik(dot)fearing(at)2ndquadrant(dot)com>
wrote:

> On 24/10/2019 16:54, Surafel Temesgen wrote:
> >
> > hi Vik,
> > On Wed, Oct 23, 2019 at 9:02 PM Vik Fearing
> > <vik(dot)fearing(at)2ndquadrant(dot)com <mailto:vik(dot)fearing(at)2ndquadrant(dot)com>>
> wrote:
> >
> >
> >
> > If we're going to be implicitly adding stuff to the PK, we also
> > need to
> > add that stuff to the other unique constraints, no? And I think it
> > would be better to add both the start and the end column to these
> > keys.
> > Most of the temporal queries will be accessing both.
> >
> >
> > yes it have to be added to other constraint too but adding both system
> > time
> > to PK will violate constraint because it allow multiple data in
> > current data
>
>
> I don't understand what you mean by this.
>
>

The primary purpose of adding row end time to primary key is to allow
duplicate value to be inserted into a table with keeping constraint in
current data but it can be duplicated in history data. Adding row start
time column to primary key will eliminate this uniqueness for current data
which is not correct

regards
Surafel