Basically Olap cube is a data structure which facilitates quick scrutiny of information. It has the possible of manipulate and analyze the data from numerous perspectives.
There was a constraint about relational databases. To overcome the limits the variety of data into cubes was in practice. Relational databases are not well matched with the next to instant study and show the large amounts of facts. As an alternative, they are better suitable for creating report from a sequence of dealings which is known as Oltp (On-Line Transaction Processing). There are many report-generating tools for the relational databases, but these are time-consuming when the whole database needs to be summarized.
Olap cubes are like the extensions of the two-dimensional array of a table. For instance a enterprise wants to investigate some economic facts by man-made goods, by time-period, by town, by type of proceeds and price, and by comparing actual data with a financial statement. The additional methods of analyzing the facts are known as dimensions. Three or more dimensions can be in Olap theory so the term hypercube is used.
The Olap cube contains numeric data which is called measures. Measures are categorized by dimensions. The cube structure may be formed from the table structure of a relational database. Measures can be obtained from the records in the fact table and dimensions can be obtained from the size tables.
An economic forecaster might want to view or he wants to make a pivot table in a variety of traditions, such as displaying all the cities down the page and all the goods across a page. This could be for a particular time, version and sort of costs. After seeing the data in this particular way the forecaster may right away wish to view it in an additional one way. The cube could fruitfully be changed so that the data displayed now has time across the page and type of price down the page. in fact this change facilitates re-summarizing of huge facts. This new outlook of the data has to be generated expertly by using Olap in order to save the analyst's time, i.e. Within seconds. A relational database and approved report-writer have taken hours to do this job.