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Re: Little question for RDM theoristes

From: Cimode <cimode_at_hotmail.com>
Date: 16 Jun 2006 04:22:36 -0700
Message-ID: <1150456956.328078.220720@u72g2000cwu.googlegroups.com>


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
U-gene wrote:
> 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 - 06:22:36 CDT

Original text of this message

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