Re: The original version
From: vldm10 <vldm10_at_yahoo.com>
Date: Wed, 29 Dec 2010 15:16:19 -0800 (PST)
Message-ID: <187a4b6f-d0b6-452e-b3cb-ebad32a243cf_at_l8g2000yqh.googlegroups.com>
Date: Wed, 29 Dec 2010 15:16:19 -0800 (PST)
Message-ID: <187a4b6f-d0b6-452e-b3cb-ebad32a243cf_at_l8g2000yqh.googlegroups.com>
> (iii)
> It is possible for two men to possess different values for a certain
> property, for the same period of time. Similarly, this can happen for
> a relationship.
Let us note that my db design can include knowledge about (real world)
attributes. So it is possible that two people have different knowledge
about one state of an entity. And my db solution can record both of
these in db.
Knowledge about an attribute of an entity depends on different
conditions. For example a shape of an entity depends of an angle of
watching.
Of course my db design can support a constraint that forces unique
entity’s attributes for one state.
Vladimir Odrljin Received on Thu Dec 30 2010 - 00:16:19 CET