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Re: [ontolog-forum] Is there something I missed?

To: "[ontolog-forum] " <ontolog-forum@xxxxxxxxxxxxxxxx>
From: "Schiffel, Jeffrey A" <jeffrey.a.schiffel@xxxxxxxxxx>
Date: Fri, 30 Jan 2009 13:46:33 -0600
Message-id: <ECF42862FCA16D41BFA98F8C45F0955405723CA6@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
> From: Patrick Cassidy    (01)

> In the RDB's I have seen, each field (column in a table) often
(typically?) 
> represents one relation on the type represented by the table, so the
number 
> of columns does not have any relation to the arity of the relations
used.
> Two or more columns can be used together to represent higher-arity 
> relations, but they may be quite independent.    (02)

I'm not certain I know what you mean. In an entity-relationship isn't
the relation the entire row, not just one column? The entity is the name
of the table. The names of the columns are the identifiers of an n-ary
relation. Each row is an instance of the n-ary relation. Or am I missing
something?    (03)

-- Jeff Schiffel    (04)

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