IST 349 Chapter 5 Concepts

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Nov 20, 2013 (3 years and 4 months ago)

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IST 349

Chapter 5 Concepts






What is the structure of a relational database?

Tables, records, fields.




What is a primary key?

A special field in a table that contains unique identifiers


no duplication of values
allowed. An example of such a field would

be “Social Security Number”




What type of a
foreign key
?

A field that appears in a table that is a primary key in another table. This field allows y
ou
to “look up” information in another table.




What is a relationship in a database?

Tables in a database m
ay be related to each other through common fields. The
relationship may be: one
-
to
-
one, one
-
to
-
many, and many
-
to
-
many.




What is a one
-
to
-
many relationship in a database?

One record in the first table is related to many records in the second table.




What is

normalization?

The process of streamlining complex groups of data to minimize redundant data and
reduce awkward many
-
to
-
many relationships.




What are some database management systems for large mainframe and midrange
computers?

DB2, Oracle, Microsoft SQL




In creating a database system using DBMS software, there are two steps in the creation
process. What are these two steps?

Describe each field and its characteristics (name, size, type, etc.) in the tables and
enter
data into the tables.




What is SQL?

Struc
tured Query Language. A language in which one defines a query. In Access, this is
done through a graphical interface. Other database systems use SQL.




What is a data warehouse?

A database that stores current as well as historical data from throughout the c
ompany.
The data originates from many different operational areas within the business and may
come from different databases and be in different formats.





What is data mining?

Data mining is a sophisticated query system that finds hidden patterns and relat
ionships
among the data. The information obtainable from data mining include: associations,
sequences, classifications, clustering, and forecasting.




Explain how databases and the web interact.

We may visit a company’s web site and check availability and p
ricing of a certain
product. The customer accesses the company’s web server. The company’s web server, in
turn, is connected to the company database server. See Figure 5.14 to see this process and
how it works.




Give an example from our text of a company
that accesses its corporate databases
through the Web.

ThomasNet.com

Facebook




What is an “information policy”?

The ‘information policy” of a company identifies which users can share which
information, where information can be distributed, and who is
responsible for updating
and maintaining the information.




Why is data quality so important to a business?

Inaccurate data can create serious operational and financial problems for a company. It is
estimated that 25 percent of the critical data
in large Fo
rtune 1000 companies’ databases
is inaccurate. Correcting these errors can lead to increased revenue.


Case Studies


Asking the Customer by Asking the Database


Main point: Large companies can find out what their customers want through data mining of
their

customer database. These databases now may include customer data gathered from social
media, hand
-
held devices, and e
-
mail transactions as well as traditional types of data (purchase
history).


Controversy Whirls Around the Consumer Product Safety Databas
e


Main point: The US Consumer Product Safety Commission has launched an online database,
located at
www.saferproducts.gov
, that contains
information submitted by consumers on
defective items that may cause inju
ry to the user. There are supporters and critics of this
database.