Online analytical processing, or OLAP is an approach to swiftly answer multi-dimensional analytical (MDA) queries.
The core of any OLAP system is an multidimensional cube OLAP cube
It consists of numeric facts called measures which are categorized by dimensions.The cube metadata is typically created from a star schema or snowflake schema of tables in a relational database.
Measures are derived from the records in the fact table and dimensions are derived from the dimension tables.
OLAP is part of the broader category of business intelligence
Typical applications of OLAP include business reporting for sales, marketing, management reporting, business process management (BPM),
budgeting and forecasting, financial reporting
OLAP tools enable users to interactively analyze multidimensional data from multiple perspectives.OLAP consists of three basic
analytical operations: consolidation, drill-down,dril-up,and slicing and dicing
Consolidation involves the aggregation of data that can be accumulated and computed in one or more dimensions
Image below highlights the MultiDimensional nature of the OLAP Cube showing a list of Products purchased by a number of Customers and the Cost implication (Measure)across a Time Period
Image of Data contained within a Cube deployed through using a Microsoft OLAP Solution
Image showing Excel2007/2010 Reporting off OLAP Cube with built-in KPIs(Key Performance Indicators)