Database Design & Management Exam 1 Review

True

Business rules help you determine the relationships that exist between entities.

primary

By default, records in a table are displayed in......key sequence.

True

Controlled redundancy makes a relational database work.

False

Conversion from a manual file system to a database system is simply a matter of importing the data into the DBMS.

Restoring the database after a failure

DBMS recovery management deals with......

Indexes

Data retrieval speed can be increased dramatically by using......

M:N

Each U.S. President may be associated with many Congresses, and any given Congress may serve with more than one President (for example, the Congress that served both J.F. Kennedy and L.B. Johnson). This is an example of which kind of relationship?

Attribute domain

Each column has a specific range of values known as the......

True

Each column in a relational table has a specific range of values known as the attribute domain.

Attribute

Each column of a a table represents a(n)......

Atrributes

Each entity has certain characteristics known as......

True

Entity integrity must exist before you can evaluate referential integrity between two tables.

Identifying appropriate entities and attributes

Good database design begins by......

Relationships between entities

In E-R diagrams which conform to the Chen convention, diamonds are used to represent?

Entities

In E-R diagrams which conform to the Chen convention, rectangles are used to represent?

True

In SQL, the difference between DDL and DML is that one defines the data structure while the other allows users to extract the data.

True

In a relational table, each table must have an attribute or a combination of attributes that uniquely identifies each row.

Row

In a table, a tuple is a(n)......

Outer JOIN

In a(n)......, the unmatched pairs would be retained and the values from the unmatched other table would be left blank or null.

Set

In network terminology, a relationship is called a......

Entity set

In the relational model, a grouping of related entities becomes a(n)......

Navigational data access environment

Like the hierarchical model, the network model provides a......

real

A data model must represent the......world as closely as possible.

False

A field filled with a null value is the same as a field filled with spaces.

Secondary key

A key used strictly for data retrieval purposes, such as customer name, is called a......

A set of one or more fields

A record consists of......

Unary

A recursive relationship, or a relationship where an entity relates to itself, is a(n)......

Ternary

A(n)......relationship exists whenever three entities are associated.

Table

According to E.F. Codd, another term for the word relation is......

True

An Entity is a person, place, or thing about which data are to be collected and stored.

A spur of the moment question

An ad hoc query is?

Crow's Foot

Another common ER modeling technique used primarily in the business sector for ERD's is......

Breaking the M:N situation up to produce a set of 1:M relationships

Problems inherent in the many-to-many relationship in a relational environment can be best avoided by......

Use

Proper database design requires the database designer to precisely identify the database's expected......

True

SQL allows the user to specify WHAT must be done, without specifying HOW it must be done.

Data

Structural independence exists when we are able to make changes in the database structure without affecting the DBMS's ability to access the......

Dictionary management

The DBMS function that stores the definitions of the data elements and their relationships, is:......

True

The E-R model is a tool which is commonly used to translate different views of data among managers, users, and programmers to fit into a common framework.

Inheritance

The ability of an object to use the attributes and methods of classes of objects in an Object-Oriented database is called......

Sharing of data in the database Promoting a clearer view of the big picture Providing better access to more and better managed data (All of the above)

The advantages of DBMS include which of the following?

Independent of both hardware and software

The conceptual model is......

End user's

The external model is best described as the......view of the data environment.

DBMS

The internal model adapts the conceptual model to a specific......

True

The most important advantage of the DBMS is its ability to let the user/designer operate in a human logical environment.

E-R

The most widely used conceptual model is the......model.

False

The order of rows and columns is extremely important to the DBMS.

JOIN

The real power behind the relational database, allowing the use of independent tables linked by common attributes, is......

every non-null foreign key value reference an existing primary key value

The referential integrity rules requires that......

Structural

The relational database allows us to ignore the structure's......complexity.

Their degree of abstraction

The separation of data models into conceptual, external, and internal is based on......

Update

The type of data anomaly that occurs when changes are made to existing records is called......

Tables

The user perceives the relational database as a collection of......in which data are stored.

1:M

The......relationship is the relational ideal and constitutes the relational database's main building block.

Hierarchical

The......structure is an ordered data arrangement that logically resembles an upside-down tree.

False

To maintain entity integrity, a null value is permitted in the primary key.

A primary key of one table appears again as a foreign key in a related table

We can describe a 1:M relationship by observing that......

Composite keys

What are keys that are composed of more than one attribute called?

It is the structural blueprint of the database

What does logical design mean?

True

When constructing database tables it is the metadata that determines the data type and column properties.

Process

Which of the following is NOT a component of the E-R data model?

Have a primary key that uniquely identifies each row

Which of the following is necessary for a table to exhibit "entity integrity"?

A data model

Which of the following is the relatively simple representation, usually graphic, of complex real-world data structures?

UNION

Which relational algebra function would combine row from two union-compatible tables into one new table.

Parent

Within the hierarchical model, the top layer or root is perceived as the......of the segment directly beneath it.

Islands of information

One drawback to a file based system that leads to potential data anomalies is:

Rows

PRODUCT produces a list of all possible......from two tables.

INTERSECT

......produces a listing that contains only the rows that appear in two union-compatible tables.

SELECT

......yields a horizontal subset of a table.

DIFFERENCE

......yields all rows in one table that are not found in the other table.

Distributed

A DBMS that supports a database located at several different sites is called a......DBMS.