CPT 200 Lesson 1 Introduction to Databases
What is a relational database?
A collection of data organized as a set of formally defined tables
What is program-data dependence?
A situation in which the data and its structure rely on the application program that accesses it
As regards a database management system (DBMS), what is managed concurrency?
A system that controls how multiple users can access data at the same time
Which of the following is a disadvantage of using file-based databases?
Application program inflexibility
What is a database management system?
Software that supports the creation and management of a database
Which of the following describes the data held in a database?
System catalog
Which of the following produced important information concerning database optimization?
The Peterlee Relational Test Vehicle
Why is storing data in a central repository advantageous?
The data is much easier to manage and manipulate
What does it mean that information is persistent?
The information remains intact after the program that accessed the information has ended.
In a file-based database, what is the difficulty caused by holding data in separate, disparate files?
The process of accessing and synchronizing multiple files becomes more complex as the number of files that need to be accessed grows.
Why does the separation of the database systems and the programs that access them make an application programmer's job easier?
The programmer no longer needs to be concerned with how the database is defined or how it holds the data
Which of the following describes file-based databases?
They generally use a decentralized approach
Because businesses rely on their database systems for mission-critical information, the data within the database should be:
organized in a manner that permits easy data retrieval
Which of the following databases is a file containing records that have no structured interrelationship?
Flat-file database
Which of the following databases is a file in which data is collected in lines of text, with each value separated by a tab character or a comma and with each row represented by a new line?
Flat-file database
Which of the following is a disadvantage of using a DBMS?
Increased complexity
Which of the following is an advantage of using a DBMS?
Increased data security
In a decentralized environment, why is the repetition of data problematic?
It is more difficult to maintain the integrity of the data
Why is adherence to standards (such as SQL) an advantage of using a DBMs?
It makes writing an application program much simpler
Why is program-data independence advantageous?
New data structures can be added to the database without the need to modify the application programs that access the data
Which of the following is a disadvantage of using a DBMS?
Cost
Which of the following can a database designer use to specify constraints on data?
Data Definition Language (DDL)
The DBMS allows users to retrieve, insert, update and delete data in the database using which of the following?
Data Manipulation Language (DML)
Which of the following is an advantage of a modern database management system (DBMS) over a file-based database?
Data is integrated into one central repository
Who among the following directs or performs all activities pertaining to maintaining a database environment?
Database administrator (DBA)