Database Management Extra 5

Question 1

The portion of the database that interacts with application programs.

Answer 1

Subschema

Question 2

A logical construct perceived to be a two dimensional structure composed of intersecting rows (entities) and columns (attributes) that represents an entity set in the relational model.

Answer 2

Table

Question 3

In the relational model, a table row.

Answer 3

Tuple

Question 4

A language based on object-oriented concepts that provides tools such as diagrams and symbols to graphically model a system.

Answer 4

UML

Question 5

A property of an OODBMS that allows the database to keep track of the different transformations performed on an object.

Answer 5

Versioning

Question 6

A description of a policy, procedure, or principle within an organization. For example, a pilot cannot be on duty for more than 10 hours during a 24-hour period, or a professor may teach up to four classes during a semester.

Answer 6

Business Rule

Question 7

A minimal superkey; that is, a key that does not contain a subset of attributes that is itself a superkey.

Answer 7

Candidate Key

Question 8

An entity designed to transform an M:N relationship into two 1:M relationships. The ??? ??? primary key comprises at least the primary keys of the entities that it connects. Also known as a bridge entity or associative entity.

*** composite key = A multiple-attribute key.

Answer 8

Composite Entity

Question 9

The role of a key. In the context of a database table, the statement “A determines B” indicates that knowing the value of attribute A means that the value of attribute B can be looked up.

Answer 9

Determination

Question 10

In data modeling, the construct used to organize and describe an attribute’s set of possible values.

Answer 10

Domain