DataminingConceptsandteniques4.ppt

* * * * * * Bit-map index compression methods should be introduced -JH * * * * * * * * * * * * * * * * ALMA MATER: To thy happy children of the future—Those of the past send greetings * * * K. Wu, E. Otoo, and A. Shoshani, Bitmap Index Compression Optimality, VLDB’04 Need to digest and rewrite it using an example! See full abstract on slide towards end of file. * * * * * * * * * * MK 08.11.09 Former title: Data Warehouse Back-End Tools and Utilities * * * * * * * * * * * * * * * * * * * * * * * Browsing a Data Cube Visualization OLAP capabilities Interactive manipulation * Chapter 4: Data Warehousing and On-line Analytical Processing Data Warehouse: Basic Concepts Data Warehouse Modeling: Data Cube and OLAP Data Warehouse Design and Usage Data Warehouse Implementation Data Generalization by Attribute-Oriented Induction Summary * Design of Data Warehouse: A Business Analysis Framework Four views regarding the design of a data warehouse Top-down view allows selection of the relevant information necessary for the data warehouse Data source view exposes the information being captured, stored, and managed by operational systems Data warehouse view consists of fact tables and dimension tables Business query view sees the perspectives of data in the warehouse from the view of end-user * Data Warehouse Design Process Top-down, bottom-up approaches or a combination of both Top-down: Starts with overall design and planning (mature) Bottom-up: Starts with experiments and prototypes (rapid) From software engineering point of view Waterfall: structured and systematic analysis at each step before proceeding to the next Spiral: rapid generation of increasingly functional systems, short turn around time, quick turn around Typical data warehouse design process Choose a business process to model, e.g., orders, invoices, etc. Choose the grain (atomic level of data) of the business process Choose the dimensions that will apply to each fact table record Choose the measure that wi