ADMS 2511 Chapter Notes - Chapter 3: Data Redundancy, Data Degradation, Query Language

• School: York University
• Department: Administrative Studies
• Course: ADMS 2511
• Professor: Mario Vasilvkos

Document Summary

First- amount of data increases exponentially with time. Much historical data must be kept for a long time, and new data are added rapidly. Data is scattered throughout the organization and are collected by many individuals using different methods and devices. Another problem- data are obtained from multiple sources- internal sources (corp. Database, and company docs), and external sources (commercial databases, gov. Reports and corp. websites: also downloaded from the web via clickstream data- produced by visitors and customers when they visit a website and click on hyperlinks. Data degrades over time- ex/ customers change addresses, or names, companies going out of business or are bought, etc. Also subject to data rot - over time there can be physical problems with storage media, making it harder to access the data. Sometimes finding machines to access data can be difficult as well. Data security, quality, and integrity are critical, yet easily jeopardized.