Understanding Drill-down Reports

As we have highlighted, grouping data facilitates data analysis for business users and enables meaningful summarizations in your reports. Having both the group level and the detail level data available in a view of a report enables the simultaneous analysis of both group level summaries and the supporting detail records (for example, database fields, formulas, and so on). There are situations, however, in which a report consumer or analyst will want to view only aggregated group level information initially and then selectively drill-down into detail records where relevant (that is, drill-down only where the aggregated group level information is interesting, appealing, or stands out). This is easily and quickly accomplished in Crystal Reports through the use of the built-in drill-down capabilities in the product.

When the term drill-down is used, it implies that a business user has the ability to move from an aggregated or grouped view of the data (for example, sales revenue for each sales district) to a more detailed level of the data (for example, sales revenue for each salesperson in a selected sales district). In Crystal Reports, this is as easy as double-clicking on the involved group data or aggregated graphic.

Creating a Drill-down Report

By default, whenever a group is created within Crystal Reports, an automatic drill-down path is created from the respective group headers into the child groups and Detail records. The drill-down icon, when the cursor icon turns into a magnifying glass, will appear in your Crystal Reports preview tab as you hover over a group header with drill-down enabled like those depicted in Figure 6.17.

Figure 6.17. A sample report with drill-down groups.

By double-clicking on the involved group header, a new viewing tab is opened with only the relevant group header's supporting information. Figure 6.18 highlights one of these views.

Figure 6.18. The Drill-down Viewing tab in Crystal Reports Preview mode.

An alternative method of navigating through report data is to use the Group Navigation tree that is exposed through all Crystal Report Viewers. The advantage of this is that it does not initiate new viewing tabs like those seen in Figure 6.18. If your report does not have a navigation tree displayed, click on the Toggle Group Tree button located on the main toolbar. The Group Navigation tree enables report viewers to quickly jump to any point in the report by highlighting the group level that they are interested in viewing.

Hiding Details on a Drill-down Report

To accomplish the task of only displaying the aggregated group level information in our sample report and not the details, right-click on the Details section either in the Design or Preview window. Figure 6.19 highlights the resulting right-click menu.

Figure 6.19. Detail Section right-click menu.

By selecting the Hide (Drill-Down OK) option in this right-click menu, our report will now only show the details within the aggregated groups when a business user drills down into them. Figure 6.20 highlights what the report now looks like in Preview mode. From here, the business user can drill-down to the drill-down viewing tabs (see Figure 6.18) by double-clicking on any of the group header rows or data.

Figure 6.20. A sample report with detail sections hidden, but available in drill-down.

The Suppress option from the same right-click menu, shown in Figure 6.19, can provide another viewing option to report designers and essentially turn off drill-down in your report. If the aggregated group level section data is to be viewed by business users but they will not be allowed to view detail section data, this can be accomplished by suppressing the detail section.