Non-First Normal Form natural join operation
I have 2 tables in non-first normal form:
What would be the result of the NATURAL JOIN operation of these two table?
It is not exactly clear what your picture is supposed to represent. I'm going to assume that R1 is a relation with three attributes, A,B and X; R2 is a relation with three attributes, E,B and X.
The natural join would be a join where the values in B and X are equal in both R1 and R2. What type of attribute is X? If X is a relation-valued attribute and the columns labelled C and D represent the tuples in X then it seems that the relation values are different in each case. (X in R1 and X in R2 happen to have some of the same tuple values in common but the values of relation X are different in each case).
So the result of the natural join would be an empty relation with a heading of A,B,E,X but with zero tuples.
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