Data Analysis Tools

Data analysis tools are used to perform complex analysis of data.They will normally have a rich set of analytic functions,which allow sophisticated analysis of data.These tools are designed for buisness analysis.
Data analysis tools can again subdivided into MOLAP tools and ROLAP tools.They came into existence because the term OLAP(On-Line Analytical Processing)has become an industry buzzword.
On-Line Analytical Processing is a decision support software that allows the user to quickly analyze information that has been summarized into multidimensional views and hierarchies.
On Line – Emphasizes live access to data, not static reporting
Analytical Processing – Ad-hoc queries, drill-down, roll-up, reporting across various dimension.
OLAP databases are also known as multidimensional databases or MDDBs.
Multidimensional analysis is a technique whereby data can be analyzed in many dimensions at once.The term dimension here means an attribute such as cost,duration or name.They are equivalent to a column in a relational table.The idea is that instead of analyzing the data in a two-dimensional table,the data is loaded into a multidimensional hypercube to be analyzed.

MOLAP(Multidimensional OLAP) tools have an SQL interface that allows them to extract data from a relational database.On a predefined set of data,MOLAP gives userfriendly,fast access to poweful analytical and statistical functions.They are good to use for analyzing aggregated data with the dimension data.It do very well in dimensional slicing.if data has been loaded into the cube dimensioned by office,region,sales-quantity,sales-value and product,the tool will be able to switch from displaying data by region to displaying data by product or by sales-value.

ROLAP(Relational OLAP) are the traditional SQL-oriented tools that have tight integration to the relational model.They are changing all the time.They use metadata to isolate the user from the complexities of the data warehouse,and to present a buisness perspective of the data.They can be used as data browsers,and will have good drill-down capability from aggregation to detailed data.