Online analytical processing (OLAP) is a category of software technology that enables analysts, managers, and executives to gain insight into data through fast, consistent, interactive access to a wide variety of possible views of information that has been transformed from raw data to reflect the real dimensionality of the enterprise as understood by the user.
Kinds of OLAP ROLAP- relational OLAP using relational databases; a star schema is used MOLAP- multidimensional OLAP using multidimensional databases DOLAP- desktop OLAP Other variations
Example: Olap Usage of an Automobile Marketer The Story An automobile marketer wants to improve business activity. Therefore he wants to view sales figures from different perspectives. A Question What is the trend in sales volumes over a period of time for a specific model and color across a specific group of dealerships ? The Data Needs Sales by model Sales by dealership Sales by color Sales over time etc.
Example: The Multidimensional View of the Data Sales Volumes BlueRedWhite Van Coupe Sedan Miller Clyde Smith COLOR DEALERSHIP MODELMODEL
OLAP Features: “Slicing and Dicing“ the Data Sales Volumes BlueRedWhite Van Coupe Sedan Miller Clyde Smith COLOR DEALERSHIP MODELMODEL Color: Blue and White Model: Coupe only Dealership: Clyde only Clyde BlueWhite Coupe “Sliced and Diced“ Data Choosing a range out of each dimension:
OLAP Features: Rotating the Data Sales Volumes BlueRedWhite Van Coupe Sedan COLOR MODELMODEL View of the Account Manager Rotate the data cube by 90° DEALERSHIP Sales Volumes MillerSmithClyde Van Coupe Sedan MODELMODEL View of the Product Manager Different users will require different views of the multidimensional cube – OLAP allows easy rotation of data
OLAP Features: Drill-Down and Roll-Up Data can be disaggregated and aggregated along a dimension according to their natural hierarchy Drill-Down Roll-Up State Region Dealership MillerSmithClydeLucas Gleason AtlantaAthens Georgia Sales Volumes by Organization Dimension - three level hierarchy -