In this recipe we will learn how a user can drill up and drill down through hierarchies and levels.
Navigating from higher level of detail to lower level of detail is called drill down. In the same way navigating from lower level of detail to higher level of detail is called drill up.
For instance, year-quarter-month-day is a hierarchy with four levels. These levels are year, quarter, month, and day. A user viewing reporting figures for a year might be interested in navigating to individual quarters, which make up that year. Similarly, he/she may want to further drill down to the month level to see monthly level of detail.
In a similar manner a user currently viewing number at day level might be interested in ...