OLAP Online Analytical Processing
OLAP(online analytical processing) is computer processing that enables a user to easily and selectively extract and view data from different points of view.
- For example, a user can request that data be analyzed to display a spreadsheet showing all of a company’s beach ball products sold in Florida in the month of July, compare revenue figures with those for the same products in September, and then see a comparison of other product sales in Florida in the same time period.
- To facilitate this kind of analysis, OLAP data is stored in a multidimensional database.
- Whereas a relational database can be thought of as two-dimensional, a multidimensional database considers each data attribute (such as product, geographic sales region, and time period) as a separate “dimension.
- An OLAP database does not need to be as large as a data warehouse since not all transactional data is needed for trend analysis.
- Using Open Database Connectivity (ODBC), data can be imported from existing relational databases to create a multidimensional database for OLAP.
The central table in an OLAP starts data model is called the fact table. The surrounding tables are called the dimensions. Using the above data model, it is possible to build reports that answer questions such as:
The supervisor gave the most discounts.
To obtain answers, such as the ones above, from a data model OLAP cubes are created. OLAP cubes are not strictly cuboids – it is the name given to the process of linking data from different dimensions.