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Bottom-up approach and Universal Relation Schema

As discussed in section 5.3.1, we will use the bottom-up design approach in our tutorial system. In fact, we assume that we have a very bad initial relational schema, i.e. a universal relational schema: all database attributes are being described by a single relation. This is good for educational purpose because we can use this example to exploit the usage of data-dependency, especially functional dependency. According to the database attributes defined in section 5.2, our initial relational schema is a universal relation schema R, such that:

R=NCFMTPDSRUAL

where N,C,F,M,T,P,D,S,R,A,L are the acronyms of the attributes defined in section 5.2.

With this schema in hand, we are able to design our examples of data-dependency.

Khan Samee Ullah
Wed Dec 19 10:27:23 CST 2001