DBMS Chapter 03 - Relational DB Model (Reading Quiz)

The _____ relationship should be rare in any relational database design.

1:1

T/F Character data can contain any character or symbol intended for mathematical manipulation.

False

T/F Only a single attribute, not multiple attributes, can define functional dependence.

False

T/F The one-to-many (1:M) relationship is easily implemented in the relational model by putting the foreign key of the "1" side in the table of the "many" side as a primary key.

False

T/F The order of the rows and columns is important to the DBMS.

False

T/F The row's range of permissible values is known as its domain.

False

_____ relationships can be implemented by creating a new entity in 1:M relationships with the original entities.

M:N

The _____ constraint can be placed on a column to ensure that every row in the table has a value for that column.

NOT NULL

_____ returns only the attributes requested, in the order in which they are requested.

PROJECT

_____ logic, used extensively in mathematics, provides a framework in which an assertion (statement of fact) can be verified as either true or false.

Predicate

To be considered minimally relational, the DBMS must support the key relational operators _____, PROJECT, and JOIN.

SELECT

T/F A null is created when you press the Enter key or the Tab key to move to the next entry without making a prior entry of any kind.

True

T/F As rare as 1:1 relationships should be, certain conditions absolutely require their use.

True

T/F Each table in a relational database must have a primary key.

True

T/F If the attribute (B) is functionally dependent on a composite key (A) but not on any subset of that composite key, the attribute (B) is fully functionally dependent on (A).

True

T/F Relational algebra defines the theoretical way of manipulating table contents using relational operators.

True

T/F The DIFFERENCE operator subtracts one table from the other.

True

T/F You can think of a table as a persistent representation of a logical relation.

True

A _____ key can be described as a minimal superkey, a superkey without any unnecessary attributes.

candidate

Each table _____ represents an attribute.

column

A _____ is the primary key of one table that has been placed into another table to create a common attribute.

foreign key

A(n) _____ only returns matched records from the tables that are being joined.

inner join

Referential _____ dictates that the foreign key must contain values that match the primary key in the related table, or must contain null.

integrity

In the relational model, _____ are important because they are used to ensure that each row in a table is uniquely identifiable.

keys

A _____ is any key that uniquely identifies each row.

superkey

The _____ is actually a system-created database whose tables store the user/designer-created database characteristics and contents.

system catalog