Please help me answer these questions related to databases. Also, provide an exp

Question

Please help me answer these questions related to databases. Also, provide an explanation for your answer.

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1. It is possible for a attribute to be multivalued in a ___________________ but not a _________________. (Fill in the blanks to get the best possible answer that can be formed using the terms ‘ER model’, ‘relational schema’, and ‘recursive relationship’.)

2. Why might you want to model ‘address’ as a composite attribute (built from attributes ‘street’, ‘city’, ‘state’, and ‘zip’, perhaps) rather than just using all of the individual attributes? Would it be a) because in the model we might want to sometimes refer to the address as a whole and sometimes to parts of the address, b) to save space, or c) to avoid possible null values ______

3. Why might it be a bad idea to model the name of an instructor’s department as an attribute of the instructor? Would it be because: a) we might in the future want to allow instructors to belong to multiple departments, b) it is important to model the smallest possible number of attributes, or c) department names can change? (select all that apply) _________

Explanation / Answer

1. It is possible for a attribute to be multivalued in a ER model but not a relational schema.

2. Why might you want to model ‘address’ as a composite attribute (built from attributes ‘street’, ‘city’, ‘state’, and ‘zip’, perhaps) rather than just using all of the individual attributes?

Ans:  c) to avoid possible null values

3. Why might it be a bad idea to model the name of an instructor’s department as an attribute of the instructor? Would it be because

Ans: a) we might in the future want to allow instructors to belong to multiple departments  

and  c) department names can change

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