Queries determine what data items appear in the report. Sometimes you want detailed rows of data, which you obtain by using a simple SELECT statement. Other times you must calculate totals or averages using summary functions and grouped columns or must apply filters to show only the data you want.
IBM® Cognos® Analytics - Reporting automatically creates the queries you need as you build reports. However, you can modify these queries or create your own custom queries to get the results you want.