Chapter 1 Flashcards
Data management
Generation, storage and retrieval of data
Information
Produced by processing data and gives it meaning.
Knowledge
Information enables knowledge
Metadata
Data about data (describes characteristics of the data and its relationships)
Database Management System (DBMS)
Collection of programs that manages the database structure and controls access to data stored within it.
It is an intermediary between the user and the database.
Data inconsistency
Different versions of the same data appear in different places
Data quality
Promoting accuracy, validity. And timeliness of data
Types of data bases:
Single-user
-Desktop database
Multi-user
-Workgroup database: supports small number of users
-enterprise database: supports many users across many departments.
Centralized database:
Data located at a single site
Distributed database:
Data is distributed across different sites.
Cloud database:
Created and maintained using cloud data services
General-purpose databases:
Contains wide variety of data used in multiple disciplines.
Discipline specific database
Contains data focused on specific subject areas
Operational database
Supports a company’s day to day operations
Analytical database
Stores historical data and business metrics used for strategic decision making
Data warehouse
Stores data in format optimized for decision support
Online analytical processing (OLAP)
Enables retrieving, processing and modeling of data from a data warehouse
Extensible mark up language
Represents data elements in textual format
Field
A character or group of characters that had a specific meaning, used to define and store data
Record
Logically connected set of fields that describe a person place or thing.
Ex: The record Customer could consist of the fields “name, address, phone number,” etc.
File
A collection of related records.
Structural dependence
Access to a file is dependent of its own structure
Structural independence
File structure is changed without affecting the applications ability to access data.
Data dependence / independence
Data changes when the data storage characteristics change.
/
Data storage characteristics are changed without affecting the program’s ability to access the data.
Islands of information
Scattered data locations (possible different versions of the same data)
Data anomaly:
Develops when not all of the required changes in the redundant data are made successfully.
Different types of the same data in different areas.
Three types of data anomaly:
Update anomaly
Insertion anomaly
Deletion anomoly
Raw data
data, not yet processed to reveal meaning.
