Visualizing Trends in Reports

 

Describes how to insert visual representations (in the form of bar graphs) of selected data directly into your report output.

To make your HTML reports more powerful, you can insert visual representations of selected data directly into the report output. These visual representations are in the form of vertical or horizontal bar graphs that make relationships and trends among data more obvious.

 

Parent topic:

IBM DB2 Web Query for System i Overview

 

Applying Bar Graphs

Vertical or horizontal bar graphs highlight relationships and trends among data.

The length of each vertical or horizontal bar graph is proportional to the magnitude of its associated data value. The shortest bar graph appears for the value with the minimum magnitude, the longest bar graph for the value with the maximum magnitude, and bar graphs of varying length appear for each value within the minimum-maximum magnitude range. Notice in the figure that a value of 147,490.00 produces a longer horizontal bar graph than a value of 50,153.00. Therefore, a complete row of vertical bar graphs or a complete column of horizontal bar graphs forms a bar chart.

You can only apply data visualization bar graphs to numeric report columns (integer, decimal, floating point single-precision, floating point double-precision, and packed). Bar graphs applied to alphanumeric, date, or text field formats are ignored.

You can display data visualization bar graphs in OLAP-enabled HTML reports, where bar graphs are applied to Measures. See Associating Bar Graphs With Measures.

 

Associating Bar Graphs With Measures

You can associate data visualization bar graphs with any numeric measure that appears in the report output.

The type of bar graph that you can apply depends on the placement of the dimensions included in the report:

For illustrations, see Applying Bar Graphs.

For more information about OLAP reports, see Analyzing Data in an OLAP Report.

 

Data Visualization Bar Graph Attributes

The following table outlines the default attributes used to display data visualization bar graphs applied from the OLAP selections pane or the OLAP Control Panel. The first column lists the bar graph attribute, while the second column lists the default value.

Bar graph attribute

Default value

Color

Positive values: Blue

Negative values: Red

Length

Vertical bar graph: 60 pixels

Horizontal bar graph: 80 pixels

Width

The size of the font in the report output is used to define a default value for the width of the bar graph.

Currently, you cannot modify bar graph attributes from the OLAP selection panel or the OLAP Control Panel.

 

Applying Bar Graphs to Measures in an OLAP Report

The quickest way to apply data visualization bar graphs to numeric measures is from the report itself.

 

Apply Bar Graphs to Measures in an OLAP Report

  1. Right-click the title of a measure column.

  2. Choose Visualize from the menu.

The report runs automatically, displaying a column of bar graphs following the selected measures column.

Tip: To remove the bar graphs, right-click the measure column title and choose Remove Visualization from the menu.

Applying and Sorting Bar Graphs in a Report

In the following OLAP report:

  1. Right-click Line Cost of Goods Sold and choose Visualize to apply a data visualization bar graph to each value in the column, as shown in the following image.

    The display changes instantly, as shown in the following image.

  2. Sort the data by highest value. You can either right-click Line Cost of Goods Sold and choose Sort by Highest, or click the Up arrow (the tool tip reads Sort LINE_COG highest to lowest).

    The following image shows the results of sorting the data by the highest value.

 

Applying Bar Graphs to Measures Using the Selections Pane or Control Panel

You can apply data visualization bar graphs to any numeric measure.

To indicate the measures for which you want to display bar graphs, you click the check box located to the left of each measure. This check box has three states that control the display modes for the measure.

In the following table the first column shows the three check box states and the second column provides descriptions for the display modes.

Check Box State

Display Mode for the Measure

Check mark

Displays the measure.

Graph icon

Applies a bar graph to the measure and displays both the measure and its associated bar graph.

Blank box

Does not display the measure or an associated bar graph.

You click the check box next to a measure until it reflects the display mode you want.

If an OLAP report contains a measure that does not appear in the report, the Measure control shows a blank check box. To display the measure, click the check box once. To display the associated bar graph, click the check box again.

The three-state check box is not active when you apply Stack Measures to your report. These features are mutually exclusive.

 

Apply Bar Graphs to Measures Using the Selections Pane

  1. From the OLAP selections pane, click the arrow to the left of the Measures control.

  2. Click the check box beside each numeric measure to which you want to add a bar graph. The check mark in the box is replaced with the Graph icon.

  3. Click Run. The new report appears with the associated bar graphs.

 

Apply Bar Graphs to Measures Using the Control Panel

  1. Click the OLAP button in the OLAP selections pane to open the OLAP Control Panel. The Measures box appears in the lower right corner.

  2. If Stack Measures is applied to the report, click the Stack Measures check box to turn off this feature.

  3. To apply data visualization bar graphs to a measure, click the check box to the left of the measure.

    To apply data visualization graphs to a non-displaying measure, click the check box twice.

    The check mark in the box is replaced with the Graph icon. This icon indicates that data visualization bar graphs are applied to the measure. (If you have not done so in step two, this also deactivates the Stack Measures feature.)

    You can apply data visualization bar graphs to as many numeric measures as you want.

  4. After you select all the measures for which you want to display bar graphs, click Run.

    The new report output appears with the associated bar graphs.

  5. To continue to modify the report (either data visualization or another OLAP configuration), click the OLAP button again.

 

Remove Bar Graphs Using the Selections Pane or Control Panel

  1. From the Measures drop-down list in the OLAP selections pane or the Measures box in the OLAP Control Panel, click the check box for any measure to which you have applied data visualization bar graphs.

    This removes the Graph icon and displays a blank check box indicating that the measure will not appear in the report output when you run the report.

  2. To display the measure, click the same check box again. A check mark appears in the box.

  3. Click Run to display the new report output, where the measure appears without its associated bar graph.
Applying Data Visualization Bar Graphs to Measures Using the Selections Pane

Suppose that you want to associate data visualization bar graphs with the Profit column in the following report in order to represent visually the differences between the Costs for and the Prices of your various Products.

You have created the following OLAP report, as shown in the following image, which displays the report data by Product Name.

To associate data visualization bar graphs with the Profit column:

  1. Click the Measures drop-down list in the report (or open the OLAP Control Panel (OCP) by clicking the OLAP button), as shown in the following image.

    The check marks indicate that the measures will appear in the report output.

  2. Click the Profit check box again. The following images shows the Measures drop-down list in the OCP with the Profit check box selected as a Graph icon.

    The Graph icon replaces the check mark. This icon indicates that the measure will appear with its associated bar graph.

  3. Click the Run button to display the new report output, as shown in the following image, visualizing the Profit values in a bar graph representation.

Notice that the report now contains a new column to the right of the Profit measure. This column displays a horizontal bar chart comprised of bar graphs that represent the individual data values for the Profit measure.

 

Display Modes in the OLAP Control Panel

The Measures box, from which you select a display mode, is located in the lower right corner of the Control Panel, as shown in the following image.

The state of each measure's check box determines how the measure appears in the report output. In this illustration:

Note that the Stack Measures option is inactive when a bar graph is applied to a measure.