Download
1 / 8

Chapter 28 - PowerPoint PPT Presentation


  • 130 Views
  • Uploaded on

Chapter 28. Overview of Data Warehousing and OLAP. Introduction, Definitions, and Terminology. Data warehouse Long-term data storage OLAP Online analytical processing DSS Decision support systems. Characteristics of Data Warehouses.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Chapter 28' - giona


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Chapter 28

Chapter 28

Overview of Data Warehousing and OLAP


Introduction definitions and terminology
Introduction, Definitions, and Terminology

  • Data warehouse

    • Long-term data storage

  • OLAP

    • Online analytical processing

  • DSS

    • Decision support systems


Characteristics of data warehouses
Characteristics of Data Warehouses

  • Modeled differently – multidimensional rather than strictly relational

  • Data is “cleaned” prior to transfer

  • Data is updated on scheduled basis, rather than as transactions happen

  • Used for making long-term business decisions, not for daily transactions


Data modeling for data warehouses
Data Modeling for Data Warehouses

  • Multidimensional models use matrices called data cubes

  • The relational data model can be cumbersome for the types of querying that is needed in a data warehouse.

  • Can query in each direction to answer questions.


Building a data warehouse
Building a Data Warehouse

  • Needs careful design

  • Terms need to be standardized

    • For instance, F/M instead of Female/Male

  • Often subdivided into dependent data marts, keeping related data physically close


Problems and open issues in data warehouses
Problems and Open Issues in Data Warehouses

  • Difficulties of Implementing Data Warehouses

  • Open Issues in Data Warehousing


Summary
Summary

  • http://en.wikipedia.org/wiki/Data_warehouse


ad