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The ternary relationship of Figure 2.13 could be replaced
by a pair of binary relationships, as shown in Figure 2.22.
Figure 2.22: Representation of Figure 2.13 using binary relationships
However, there is a distinction between the two representations:
- In Figure 2.13,
relationship between a customer and account can be made only if
there is a corresponding branch.
- In Figure 2.22, an account can be related to
either a customer or a branch alone.
- The design of figure 2.13 is more appropriate, as
in the banking world we expect to have an account relate to both a
customer and a branch.
Page created and maintained by Osmar R. Zaï ane
Sun Sep 10 17:02:35 PDT 1995