Can anyone help me this problem, thanks!! Based on the following universal relat

Question

Can anyone help me this problem, thanks!!

Based on the following universal relation about a school database and the functional dependencies among attributes, answer the following questions in (a) through (c) and normalize the relation into normal forms according to the following steps ((d) through (f))- Functional dependencies: SID rightarrow SNAME, SID rightarrow MAJOR, SID rightarrow MINOR, (SID, MAJOR) rightarrow DID, DID rightarrow DNAME, DID rightarrow DCHAIR, DID rightarrow DBUDGET, DID rightarrow COFFICE. Name the problem of storing the entire universal relation in the database. (b) If the value of the attribute "coffice'' of record (sid = 001) is changed to "302A". what problem will happen? If SID is selected as a key, why is it impossible to create a new department with DID = 12, DNAME = "BIO"? Based on the universal relation, design relation schemas in INF (but not 2NF). Continue (a), design relation schemas in 2NF (but not 3NF). Continue (b). design relation schemas in 3NF ifDCHAlR COFFICE is added

Explanation / Answer

(a) The problem of storing the entire universal relation in the database is, every attribute name must be unique, and also it must be made sure that each attribute in a relation R will appear in at least one relation schema Ri in the decomposition so that no attributes are lost. This is called attribute preservation. As the attributes are functionally dependent, the decomposition may be lossy. So the problem with attribute preservation may occur (b) If the value of the attribute coffice is changed, then the normalizations in the database may need to be changed as there are dependencies among the attributes DID, DNAME, DCHAIR, DBUDGET and DCOFFICE (c) As there is no direct relationship of SID with DID and DNAME, and the attributes, SID and MAJOR make a foreign key, using the attribute SID, new department with DID and DNAME values cannot be created.

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