Re: Little question for RDM theoristes
Date: 16 Jun 2006 04:22:36 -0700
Your question is confusing...
when you ask
<<Two relations (relvalues) exists. These relations have different headers (schemas). Are these relvalues the values of different types?
The tenure of your question seems to indicate you confuse a relvar and its projection as a table....These are 2 different concepts...
..relvars do not have header..header is associated to a projection as a
human need for interpretation. only the body of the table represents a
projection of a relvar...
a relvar can define a type only if it has set of operators associated to it...(see data type definitions). In case the operators and other data type prereq are defined... 2 different relvars are necessarily are possibly defining 2 separate types.
as long as
> Two relations (relvalues) exists. These relations have different
> headers (schemas). Are these relvalues the values of different types?
> IMHO all relvalues have the same type and the headers is just data. May
> be it is special kind of data which is different from rel.bodies' data.
> . But persons exist who think in other way - if relvalues have
> different headers they are values of different types. So I'll glag to
> hear your opinions.
Received on Fri Jun 16 2006 - 13:22:36 CEST