Re: ID field as logical address
Date: Mon, 1 Jun 2009 15:27:46 -0400
Message-ID: <TYVUl.34413$ZP4.29161_at_nlpi067.nbdc.sbc.com>
"Kevin Kirkpatrick" <kvnkrkptrck_at_gmail.com> wrote in message
news:895891d5-fe55-478d-81d7-e984bc37fff9_at_r13g2000vbr.googlegroups.com...
> On Jun 1, 11:39 am, "Brian Selzer" <br..._at_selzer-software.com> wrote:
> > "Kevin Kirkpatrick" <kvnkrkpt..._at_gmail.com> wrote in message
> >
> > news:670a228b-b752-47eb-b2e4-68c966c449d9_at_s31g2000vbp.googlegroups.com...
> >
> > > What is the poor HR person to do when Mary Smith returns from a week
> > > long Vegas trip and reports that she'd gotten married on Monday and
> > > divorced on Friday?
> >
> > That should be obvious: issue two updates in succession, one for each
> > event.
>
> Am I reading that right? You think the data entry person should
> enter, as a fact to the database, "Mary Smith is currently Married",
> at a time when Mary Smith is definitely not married?
Yes, you're reading that right. The data entry person should enter, as a fact into the database, "Mary Smith got Married", at a time when it is true that Mary Smith got Married, and then "Mary Smith got Divorced" at a time when it is true that Mary Smith got Divorced. The database has to be informed that a marriage occurred and then that a divorce occurred, since it is not just states that are being constrained, but changes of state. Received on Mon Jun 01 2009 - 21:27:46 CEST