Data drill in and drill up

When working with dimensional or dimensionally-modeled relational (DMR) data sources, you can create reports that allow the reader to view more general or more detailed information on your data within a predefined dimensional hierarchy (such as Years - Year - Quarter - Month) without having to create different reports.

You can link groups of data items from different queries so that when you drill up or drill down in one query, the data item also drills up or drills down in the linked queries. Linking data items is useful if your report includes more than one query with the same data item. For example, if your report shows a list and a crosstab that each include the Product Line data item, you can link the Product Line data item from the crosstab query to the Product Line data item from the list query so that when you drill up in the crosstab Product Line data item, the list Product Line data item also drills up.

Drill down means to move from summary information to detailed data by focusing in on something. In a GUI-environment, "drilling-down" may involve clicking on some representation in order to reveal more detail.

To drill down through a series of folders, for example, on a desktop means to move through the hierarchy of folders (from the top downwards) to find a specific file or to click through drop-down menus in a GUI. Clicking on an item moves you to a level of greater detail. When an online user accesses more and more pages of the website, he or she may delve deeper into the content of the site. As a web-surfer goes further into a website, he or she goes deeper into the back pages and thus deeper into data. (Of course, he or she could also begin—for example via an external search engine—at a detailed view, and drill up to the front page of the site.)

Drilling down through a database involves accessing information by starting with a general category and moving through the hierarchy: from category to file/table to record to field. When one drills down, one performs de facto data analysis on a parent attribute. Drilling down provides a method of exploring multidimensional data by moving from one level of detail to the next. Drill-down levels depend on the data granularity.

The field of managerial economics uses the term "Drill Down" to explain exciting but technical aspects of operations research and regression analysis.