1. An instance of a relation that satisfies all real world constraints is known as?

a) Proper relation

b) Ideal relation

c) Perfect relation

d) Legal relation

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2. If K → R then K is said to be the _______ of R

a) Candidate key

b) Foreign key

c) Super key

d) Domain

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3. X → Y holds on a schema k(K) if?

a) At least one legal instance satisfies the functional dependency

b) No legal instance satisfies the functional dependency

c) Each and every legal instance satisfies the functional dependency

d) None of the mentioned

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4. X→ Y is trivial if?

a) X ⊂ Y

b) Y ⊂ X

c) X ⊇ Y

d) None of the mentioned

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5. Which of the following is not a condition for X→ Y in Boyce codd normal form?

a) X → Y is trivial

b) X is the superkey for the relational schema R

c) Y is the superkey for the relational schema R

d) All of the mentioned

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6. Which of the following is used to express database consistency?

a) Primary keys

b) Functional dependencies

c) Check clause

d) All of the mentioned

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7. Which of the following is not a condition for the third normal form in the case of XY?

a) X→ Y is trivial

b) X is the superkey for R

c) Each attribute in Y-X is a candidate key for R

d) Each attribute in X-Y is a candidate key for R

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8. F+ is called as the ________ of F

a) Closure

b) Sum

c) Cartesian product

d) None of the mentioned

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9. State true or false: A functional dependency must first satisfy the second normal form to satisfy the third normal form.

a) True

b) False

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10. State true or false: The fourth normal form does not exist and it is instead called as the BCNF.

a) True

b) False