2. Data Warehousing 4 Definition of Data Warehouse 4 Architecture of Data Warehouse 4 Different Data Warehousing Tools 4 Summary

3. What is a Data Warehouse ? 4 An organized collection of data that is – integrated from many sources other internal databases and files the internet commercial databases, etc. –consistent –subject - oriented –time-variant –non - volatile –designed for management decision support

4. Data Sources

5. Subject Orientation --Conventional database supports a function e.g. order entry, inventory, payroll -- DW organized around major subjects e.g. customer, vendor, product, activity

6. Data Warehouse vs. Application World 4 Subject Orientation 4 Excludes data that will not be used for DSS processing 4 Spans a long spectrum of time 4 Functional Orientation 4 Contains data to satisfy immediate processing requirements.

7. Consistent 4 Consistent naming conventions –e.g. Use “Customer”, not Client or Patron 4 Consistent coding scheme –e.g. M or F for gender (not 0,1) 4 Consistent in measurement variables –e.g. Miles, not Kilometers

8. Structure of a Data Warehouse AcquisitionStorageAccess Data Extraction & Cleaning Servers Analysis Querry/ Reporting Data Maining EIS Source D / B PC Data Import / Export Data Mining Appln.

9. Components of Data Warehouse 4 Data Importing Component -- Data Extraction : Actual copying of data from its source & placing it within process area --Data Cleaning Identifying the inconsistencies and incorrect data, and correcting --Data Formatting : Preparing the data in a way that is acceptable to the warehouse

10. Data Mining 4 Allow end user to have direct access and manipulation of data. -- Tools: Query managers and report writers, Statistical analysis tools

11. Different Data Warehousing Tools Selection of Vendors 4 OLAP 4 Data Extraction 4 Data Mining 4 Executive Information System 4 Financial & Marketing Tools 4 Query & Reports

12. Example 4 Assemble hundreds of versions of the same ad 4 switch & reassemble products & prices 4 Cigarette makers –some of most advanced database marketing –direct mail, discount coupons, freebies –have built databases on smoker demographics –anticipate market changes, target promotions