Chapter 1 - Intro To Database Flashcards
Database
A collection of data organized to provide efficient management of the data as well as easy access to and updating of the data.
Flat file database
A file containing records that have no structured interrelationship.
Name the problems of a flat file database
Repetition of data, separation of data, incompatibility of files, data dependence and inflexibility of the application programs that access the data.
What approach does the flat file database use?
Decentralized
How does a flat file database collect the data?
In lines of text with each value separated by a tab character or a comma And with each row represented by a new line.
System catalog or data dictionary
Part of the database that describes the data in the database.
What type of structure does a database use?
Tabular
Program data independence
Application programs that are written to access the database need not be concerned with how the database is defined or how it holds the data. Because the data is stored in a separate mechanism application programs also become completely independent entities.
What type of definitions are in object oriented programming?
Internal and external definition.
What kind of approach does database allow?
Centralized
Relational database
A collection of data organized as a set of formally described tables.
Database management system
Allows users to define create and maintain databases while providing controlled access to the database.
SQL Stands for what?
Structured query language
Structured query language
A language used to create professional high-performance corporate databases.
DDL
Data definition language
Data definition language
Permits the database designer to specify the data types held in the database as well as constraints on the data.
DML
Data manipulation language
Data manipulation language
Allows users to retrieve, insert, update and delete data in the database.
What are the five advantages of using a DBMS?
- Provides a security system.
- Provides in integrity system for preserving the consistency of the data.
- Provides a concurrency control system for shared access of the database.
- Provides a recovery system for restoring the database to a previous state in case of hardware or software failure.
- Provides a data dictionary for describing the data within the database
Database administrator
The person who directs or performs all activities related to maintaining a database environment.
View
A view is a subset of the data in a database views are useful when users do not need to see or access all of the data in the database.
Why is repetition of data needed in a database?
To improve performance and most important, redundant data is needed to model data relationships.
Name the 10 advantages of using a DBMS.
- Management of data redundancy.
- Consistency of data.
- Data sharing.
- Increased data integrity.
- Increased data security.
- Adherence to standards.
- Increased data access.
- Increased productivity.
- Managed concurrency.
- Increased data backup and recovery.
Name four of the disadvantages of using a DBMS.
- Complexity.
- Size of the software.
- Cost.
- Increased impact in case of DBMS failure.
Who proposed the first relational data model in 1970?
Dr. E. F. Codd
What was the name of the first IBM Proto typical relational database?
System R
What products came out of the system R project?
DB2, SQL/DS from IBM and Oracle.
What project took place at the University of California at Berkeley around the same time as the system R project?
The interactive graphics retrieval system. INGRES
In 1976 the IBM UK scientific center developed what project?
The Peterlee Relational Test Vehicle.
