Review Questions Chapter 1 and 2

3544 Words Feb 5th, 2014 15 Pages
Chapter 1
Review Questions (1.1 - 1.7)

1.1 Define the following terms: data, database, DBMS, database system, database catalog, program-data independence, user view, DBA, end user, canned transaction, deductive database system, persistent object, meta-data, and transaction-processing application.
a) Data: Known facts that can be recorded and that have implicit meaning.
b) Database: Collection of related data.
c) DBMS: Is a collection of programs that enables users to maintain a database.
d) Database system: Is a compilation of the database and complete definition of the database structure and constrains.
e) Database catalog: contains information such as the structure of each file, the type and storage format of each data item,
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Briefly discuss each.
a) Self-describing nature of a database system: The database system contains not only the database itself but also a complete definition or description of the database structure and constraints.
b) Insulation between programs and data, and data abstraction: In traditional file processing, the structure of data files is embedded in the application programs, so any changes to the structure of a file may require changing all programs that access that file. By contrast, DBMS access programs do not require such changes in most cases. The structure of data files is stored in the DBMS catalog separately from the access programs.
c) Support of multiple views of the data: A database typically has many users, each of whom may require a different perspective or view of the database. In todays database systems you can customize the views to better support the users.
d) Sharing of data and multiuser transaction processing: database systems allow multiple users to access the database at the same time. But in order to perform multiples transactions at the same time concurrency control software most be added to ensure that several users trying to update the same data do so in a controlled manner so that the result of the updates is correct

1.3 Discuss the main characteristics of the database approach and how it differs from traditional file systems.

A number of characteristics distinguish the database approach from the much
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