Database 3

Given the functional dependency (A, B) → C, (A, B) is a(n) ________.

C) determinant D) composite determinant Correct Response C and D

Which of the following is true about the functional dependency (A, B) → (C, D)?

A and B together determine D.

A combination of two or more columns used to identify particular rows in a relation is a ________.

composite key

If the removal of facts about one entity results in the unintentional loss of data about another entity, this is referred to as a(n) ________.

deletion anomaly

Given the functional dependency A → (B, C), A is a(n) ________.

determinant

A tuple is also known as a ________.

Row

Suppose that you need to update one value of the column SalesCost in a relation. The way the relation is constructed, this value actually needs to be changed in three different rows. However, you only change the value in two of the rows. You have just created a(n) ________.

update anomaly

A relation is in Boyce-Codd normal form (BCNF) if and only if it is in 3NF and ________.

every determinant is a candidate key

An attribute is also known as a ________.

field

Saying that two entities are functionally dependent means that ________.

for one of the entities, if we are given the value of that entity, we can determine the value of one other entity

A key consisting of one or more columns that is a primary key in another relation is a ________.

foreign key

Referential integrity constraints are used to limit the possible values of a ________.

foreign key

In general, each relation should have ________.

one and only one them

When designing a database, one of the candidate keys in a relation is selected as the ________

primary key

A ________ is used to limit the possible values of a foreign key.

referential integrity constraint

An artificial column added to a relation to serve as the primary key is a ________.

surrogate key

A relation is in third normal form (3NF) if and only if it is in 2NF and ________.

there are no non-key attributes determined by another non-key attribute

A relation ________.

A) has rows containing data about an entity B) has cells that hold only a single value C) has no two identical rows D) has columns containing data about attributes of the entity E) Correct Response All of the above.

A relation is in second normal form (2NF) if and only if it is in 1NF and ________.

all non-key attributes are determined by the entire primary key

If a table is designed so that every determinant is a candidate key, then that relation is in ________.

Boyce-Codd Normal Form

Given the functional dependency (A, B) → C, then ________.

A) B → A B) B → C C) A → B D) A → C E) Correct Response None of the above is correct

Which of the following is true about the functional dependency A → (X, Y)?

A) A determines Y. B) X and Y are functionally dependent on A. C) A is a determinant. D) X is functionally dependent on A. E) Correct Response All of the above.

A table that meets the definition of a relation is in ________.

First Normal Form

If a relation is in BCNF, and each multivalued dependency has been moved to a relation of its own, then the first relation is in ________.

Fourth Normal Form

A combination of one or more columns used to identify particular rows in a relation is a ________.

Key