Explain the functionality of OLAP. - Multidimensional analysis:- OLAP helps the user gain an insight on the data coming from different sources.
- OLAP helps faster execution of complex analytical and ad-hoc queries.
- Allows trend analysis periodically.
- Drill down abilities.
Explain the functionality of OLAP.OLAP functionality is performed using SQL Anywhere by utilizing various extensions to SQL statements and window functions. Multidimensional data analysis, data mining, trend analysis, goal seeking, cost allocations, time series analyses and altering exceptions can be performed with a single SQL statement.
Extensions to SELECT statement: Grouping input rows, analyze the groups and including the findings in the final result, are the operations that could be done in SELECT statement. They include extensions to GROUP BY clause – GROUING SETS, CUBE and ROLLUP clauses and WINDOW clause.
WINDOW aggregate functions: Configurable sliding window concept is supported for using aggregate functions, which moves down the input rows as they are processed. Computing percentiles, moving averages and cumulative sums are performed in a single SQL statement, which reduces the complexity of using self-joins, correlated sub queries, temporary tables and at times, the combination of all these three.
Window ranking functions: These functions facilitates to form a single statement SQL queries , to obtain the information , like shipped top ten products in a given year by total sales.