FUNDAMENTALS OF COMPUTER

Detailed explanation-1: -Roll-up: (Aggregate, Consolidate) A roll-up involves computing all of the data relationships for one or more dimensions. To do this, a computational relationship or formula might be defined.

Detailed explanation-2: -OLAP consists of three basic analytical operations: consolidation (roll-up), drill-down, and slicing and dicing. Consolidation involves the aggregation of data that can be accumulated and computed in one or more dimensions.

Detailed explanation-3: -OLAP stands for Online Analytical Processing Server. It is a software technology that allows users to analyze information from multiple database systems at the same time. It is based on multidimensional data model and allows the user to query on multi-dimensional data (eg.

Detailed explanation-4: -There are 3 main types of OLAP systems: ROLAP, MOLAP, and HOLAP. ROLAP uses relational databases, MOLAP uses multidimensional arrays, and HOLAP takes use of both ROLAP and MOLAP systems. OLAP cube provides various operations to gain insights on data. These include Drill-down, Roll-up, Dice, Slice, and Pivot.

Detailed explanation-5: -The drill-down operation (also called roll-down) is the reverse operation of roll-up. Drill-down is like zooming-in on the data cube. It navigates from less detailed record to more detailed data. Drill-down can be performed by either stepping down a concept hierarchy for a dimension or adding additional dimensions.