Database Management Quiz Lesson 3

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Which of the following is true about the functional dependency (A, B) → (C, D)? C and D together determine A. A and B together determine D. A and B together are determined by C and D together. A is the determinant of C.

A and B together determine D.

Given the functional dependency (A, B) → C, then ________. A and B together → C A → C B → A Both A and B together → C and A → C are correct

A and B together → C

Which of the following is not true about a relation? Can have two identical rows Has columns containing data about attributes of the entity Has cells that hold only a single value Has rows containing data about an entity

Can have two identical rows

A determinant that determines all the other columns in a relation is a ________. record candidate key surrogate key foreign key

candidate key

A combination of two or more columns used to identify particular rows in a relation is a ________. surrogate key composite key foreign key record

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) ________. update anomaly deletion anomaly normalization anomaly insertion anomaly

deletion anomaly

Given the functional dependency A → (B, C), A is a(n) ________. composite determinant determinant dependent variable independent variabl

determinant

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 deletion anomaly insertion anomaly normalization anomaly

update anomaly

A relation is in domain/key normal form if ________. every constraint on the relation is a logical consequence of the definition of keys and domains every key of the relation is a logical consequence of the definition of constraints and determinants every constraint on the relation is a logical consequence of the definition of keys and determinants every key of the relation is a logical consequence of the definition of constraints and domains

every constraint on the relation is a logical consequence of the definition of keys and domains

A relation is in Boyce-Codd normal form (BCNF) if and only if it is in 3NF and ________. every attribute is a candidate key all non-key attributes are determined by the entire primary key every determinant is a candidate key there are no non-key attributes determined by another non-key attribute

every determinant is a candidate key

An attribute is also known as a ________. field relation table row

field

Saying that two entities are functionally dependent means that ________. the entities are always connected by a mathematical equation for one of the entities, if we are given the value of that entity, we can determine the value of one other entity the functional dependency will have to be removed through normalization for both of the entities, if we are given the value of one entity, we can determine the value of the other entity

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 ________. composite key candidate key foreign key surrogate key

foreign key

Referential integrity constraints are used to limit the possible values of a ________. composite key candidate key foreign key surrogate key

foreign key

Having to enter facts about two entities when we want to enter facts about only one is an example of ________. update anomaly insertion anomaly deletion anomaly normalization anomaly

insertion anomaly

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

key

A relation is in fourth normal form if it is in BCNF and it has no ________. partial dependencies multivalued dependencies deletion dependencies transitive dependencies

multivalued dependencies

In general, each relation should have ________. one and only one theme one or two themes exactly two themes one or more themes

one and only one theme

When designing a database, one of the candidate keys in a relation is selected as the ________. composite key foreign key surrogate key primary key

primary key

A ________ is used to limit the possible values of a foreign key. composite key referential integrity constraint functional dependency surrogate key

referential integrity constraint

A tuple is also known as a ________. : row relation table field

row

The only reason(s) for having relations is to ________. store instances of functional dependencies store equation components store equation results Both store equation components and store equation results are correct

store instances of functional dependencies

An artificial column added to a relation to serve as the primary key is a ________. composite key candidate key foreign key surrogate key

surrogate key

A relation is also known as a(n) ________. relationship table attribute tuple

table

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 all non-key attributes are determined by the entire primary key every attribute is a candidate key every candidate key is a determinant

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

A relation is in second normal form (2NF) if and only if it is in 1NF and ________. every attribute is a candidate key there are no non-key attributes determined by another non-key attribute all non-key attributes are determined by the entire primary key every candidate key is a determinant

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

Given the functional dependency (A, B) → C, (A, B) is a ________. dependent variable determinant composite determinant Both determinant and composite determinant are correct

Both determinant and composite determinant are correct

If a table is designed so that every determinant is a candidate key, then that relation is in ________. Third Normal Form Boyce-Codd Normal Form First Normal Form Second Normal Form

Boyce-Codd Normal Form

A table that meets the definition of a relation is in ________. Boyce-Codd Normal Form Second Normal Form Third Normal Form First Normal Form

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 Third Normal Form Domain/key normal form Boyce-Codd Normal Form

Fourth Normal Form

Which of the following is true for a relation? The order of the columns is important. More than one column can use the same name. Entities in a column vary as to kind. The order of the rows is unimportant.

The order of the rows is unimportant.

Which of the following is NOT true about the functional dependency A → (X, Y)? X and Y together determine A. A determines Y. X and Y are functionally dependent on A. X is functionally dependent on A.

X and Y together determine A.


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