If a report has one or more dimension columns, the order in which you select and insert the columns determines the group level. For example, if you select and insert Product Line before Country, Product Line is a higher level, or outer group. Country is the lower level, or inner group. After you select the dimension columns, you can modify their order in Table Builder.
A grouped dimension column displays subtotals for the data in each group. When you group a dimension column, Report Studio eliminates duplicate data values when calculating aggregate data. Figure 4‑9 displays a summary table containing three dimension columns. The Order Date column is grouped in quarterly intervals, and is located in the innermost position.
When a summary table contains more than one dimension column, data in the outer dimension columns can be grouped, as shown in Figure 4‑9, and subtotals are displayed for each value in the grouped column.
Figure 4‑9 Grouping the innermost date‑and‑time dimension column
When working with a dimension column that contains date‑and‑time data, you can group the data by intervals such as day, week, month, quarter, or year. When placed in the innermost position, dimension columns that contain other types of data cannot be grouped, as shown in Figure 4‑10. If a dimension column contains date‑and‑time data, you can always group data in the column by intervals.
Figure 4‑10 Grouping dimension columns
The innermost dimension column does not display subtotals, irrespective of the type of data in the column, as shown in Figure 4‑9 and Figure 4‑10.
For a summary table containing a single dimension column, and one or more associated attribute columns, you cannot group data in the dimension column. No subtotals appear. The summary table displays a grand total value for all product lines, as shown in Figure 4‑11.
Figure 4‑11 A summary table displaying a grand total
The preceding summary table results from the data object, as shown in Figure 4‑12, which contains the Product Line dimension and two associated attribute fields, Product Code and Product Name.
Figure 4‑12 Examining a data object containing a dimension with multiple attribute fields
In a summary table, dimension columns can be moved only among other dimension columns. Dimension columns can also contain associated attribute fields. You cannot move a dimension column independently of its associated attribute columns. Dimension columns and associated attribute columns always appear preceding the measure columns in a summary table.
When you delete a dimension column containing associated attributes from a summary table, the attribute fields still remain.
