This is class Database System Concepts. (please use Fundamentals of database sys

Question

This is class Database System Concepts. (please use Fundamentals of database systems book(7th Edition))

1) Algebraic Operators in Relational Algebra are for....(choose all that apply)

a. Aggregation

b.Finding differences in sets

c.Matching records on key and foreign key booleans

d.Using boolean conditions to limit columns

e.Using boolean conditions to limit rows

d.Using lists to order and specify output

e.Using functions to do math with data.

2) When I write a relational algebra statement that performs aggregation, what must I be sure to include on the left side of the equation?

3) The Relational Model refers to defined terms, symbols and mathematical descriptions to document structures, constraints and output from a database system.

a. TRUE

b. FALSE

4) In relational algebra, (S - R) gives me what set of data?

5) JOIN symbols are used to combine....(choose all that are true)....

a. Same real world entities

b.Different real world entities

c.Selected columns and rows from tables.

d.None of the above

6) SET symbols in Relational Algebra are used to represent EER concepts from our design.

a. TRUE

b. FALSE

7) What does the term ROLE mean with respect to the relational model?

8) What is the output of a right outer join?

Explanation / Answer

1.all

2.should use the aggregate operation keyword I.e sum() or avg() or min()

3.TRUE

4.tuples in S but not in R

5.a and c

6.TRUE

7.role is collection of number of privelages that can be assigned to users .access is restricted using the roles

8.the output of right outer join is it contains all tuples of the right table and matching data of the left table.

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