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Meaning of 1:1, 1:1 generalization, 1:n, 1:n non identifying, n:m

Hi All,

I've been taking a look at DB Designer 4, and looking through the
documentation (http://www.fabforce.net/dbdesigner4/doc/index.html) I am a
little unclear on some of their nomenclature:

'1:1' - Ok, one to one. Got it.
'1:1 generalization' - Don't know this. Obviously different somehow from
one to one, but how?
'1:n' - One to many, I assume.
'1:n non identifying' - Nonidentifying? What does this mean?
'n:m' - Many to many? Again, not sure.

Can anyone help clarify?

Thanks!
-Josh
Jul 20 '05 #1
0 1546

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