Codd's Information Principle

From: paul c <toledobythesea_at_oohay.ac>
Date: Wed, 28 Oct 2009 19:51:26 GMT
Message-ID: <2h1Gm.50615$PH1.9648_at_edtnps82>

I can't remember where in his papers Codd stated the Information Principle but here's a version of a quote by Date: "The entire information content of a relational database is represented in one and only one way: namely, as attribute values within tuples within relations."

Recently there has been mention of logical connectors being implicit in tuples, eg. Mr. Scott wrote: "Each row of the join represents a conjunction of propositions, one for each operand", ie., what I think is called a compound proposition. I sometimes write similar, as well regarding disjunctions. But usually my purpose is simply to understand the algebra.

I would like to ask where is the "information" to the effect that certain rows represent compound propositions recorded? Received on Wed Oct 28 2009 - 20:51:26 CET

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