On-line Analytical Processing (OLAP) is a category of software technology that enables analytics, managers and executives to gain insight into data through fast, consistent, interactive access in a wide variety of infomation that has been transformed from the raw data to reflect the real dimensionality of the enterprise as understood by the user.
OLAP was introduces by Dr.E.F.Codd in 1993 and he presented 12 rules regarding OLAP:
- Multidimensional Conceptual View:
Multidimensional data model is provided that is intuitively analytical and easy to use. A multidimensional data model decides how the users perceive business problems.
It makes the technology, underlying data repository, computing architecture and the diverse nature of source data totally transparent to users.
Access should provided only to the data that is actually needed to perform the specific analysis, presenting a single, coherent and consistent view to the users.
- Consistent Reporting Performance:
Users should not experience any significant degradation in reporting performance as the number of dimensions or the size of the database increases. It also ensures users must perceive consistent run time, response time or machine utilization every time a given query is run.
- Client/Server Architecture:
It conforms the system to the principles of client/server architecture for optimum performance, flexibility, adaptability and interoperability.
- Generic Dimensionality:
It should be ensured that very data dimension is equivalent in both structure and operational capabilities. Have one logical structure for all dimensions.
- Dynamic Sparse Matrix Handling:
Adaption should be of the physical schema to the specific analytical model being created and loaded that optimizes sparse matrix handling.
- Multi-user Support:
Support should be provided for end users to work concurrently with either the same analytical model or to create different models from the same data.
- Unrestricted Cross-dimensional Operations:
System should have abilities to recognize dimensional and automatically perform roll-up and drill-down operations within a dimension or across dimensions.
- Intuitive Data Manipulation:
Consolidation path reorientation, drill-down and roll-up and other manipulations to be accomplished intuitively should be enabled and directly via point and click actions.
- Flexible Reporting:
Business user is provided capabilities to arrange columns, rows and cells in manner that gives the facility of easy manipulation, analysis and synthesis of information.
- Unlimited Dimensions and Aggregation Levels:
There should be at least fifteen or twenty data dimensions within a common analytical model.