Q1. What is OLAP?
Ans1. OnLine Analytical Processing is a software technology that empowers analysts, managers and executives a fast, consistent, interactive access to a variety of possible views of information.
Q2. What are the functionalities of OLAP?
Ans2. Functionalities of OLAP are-
• Slicing and Dicing
Q3. List different types of OLAP servers?
Ans3. There are three main types of OLAP servers-
• ROLAP – Relational OLAP stores all the information in the form of tables. This will normally include the calculations as well and put no limitations on storing data.
• MOLAP – Multidimensional OLAP stores data in the form of cubes which provides the best level of performance. It provides various views for analysis.
• HOLAP – Hybrid OLAP is the combination of both ROLAP and MOLAP.
Q4. What is the difference between OLAP and DSS?
Ans4. DSS (Decision Support System) helps in taking decisions for top executive professionals. Data accessing, data manipulation of an enterprise’s internal / sometimes external data is emphasized by DSS. The manipulation is done by tools that are task specific for providing additional functionality.
OLAP (Online Analysis Processing) is capable of providing highest level of functionality and support for decision which is linked for analyzing large collections of historical data. The functionality of an OLAP tool is purely based on the existing / current data.
Q5. What are the main features of OLAP?
Ans5. Main features are-
• Multidimensional: It provides services in variety of possible views.
• Easy to understand: The data designed for its analysis will be handled by business logic and statistical analysis which is relevant to the developer and / application user making it quite easy for end users.
• Interactive: It supports the business information through comparative data to the user. Users are encouraged for defining new ad hoc calculations which is a part of the analysis.
• Fast: It’s services are implemented in a multi-user client / server architecture and provide rapid responses to queries consistently, irrespective of database complexity.
Q6. List applications of OLAP?
Ans6. Some applications are-
• Market share analysis
• Trend analysis
• Tax planning
• Financial consolidations
Q7. Explain Roll-up operation.
Ans7. It is performed by either reducing the dimension or stepping up operation. It enables user to view summarized data in reduced dimension.
Q8. Explain Drill-down operation.
Ans8. It is performed by either increasing the dimension or stepping down operation. It enables user to view detailed data. It is also known as roll down operation.
Q9. Explain Slicing and Dicing operation.
Ans9. Slicing is process of extracting the sub cube of related information and dicing is the analysis of that sub cube.
Q10. Explain pivot operation.
Ans10. Pivot means rotation i.e. viewing the cube from different angles.