Olap, Data Marts and Warehouses, Three-Tier Architecture and Asp

WEEK 4 INDIVIDUAL PAPER

OLAP, DATA MARTS AND WAREHOUSES,

THREE-TIER ARCHITECTURE AND ASP

DBM405

OLAP, Data Marts and Warehouses, Three-Tier Architecture and ASP

OLAP

The term OLAP stands for ‘On-Line Analytical Processing’. OLAP is a technology used to process data a high performance level for analysis and shared in a multidimensional cube of information. The key thing that all OLAP products have in common is multidimensionality, but that is not the only requirement for an OLAP product.

An OLAP application is targeted to deliver most responses to users within about five seconds, with the simplest analyses taking no more than one second and very few taking more than 20 seconds. Impatient users often assume that a process has failed if results are not received with 30 seconds, and they are apt to implement the ‘3 finger salute’ or ‘Alt+Ctrl+Delete’ unless the system warns them that the report will take longer. Even if they have been warned that it will take significantly longer, users are likely to get distracted and lose their chain of thought, so the quality of analysis suffers. This speed is not easy to achieve with large amounts of data, particularly if on-the-fly and ad hoc calculations are required. A wide variety of techniques are used to achieve this goal, including specialized forms of data storage, extensive pre-calculations and specific hardware requirements, but a lot of products are yet fully optimized, so we expect this to be an area of developing technology. In particular, the SAP Business Warehouse is a full pre-calculation approach that fails as the databases simply get too. Likewise, doing everything on-the-fly is much too slow with large databases, even if the most expensive server is used. Slow query response is consistently the most often-cited technical problem