Planning to use report parameters
Before creating parameters for a report, decide what field values the report user needs to be able to specify and how to prompt the user for those values.
*Think of the different ways in which a user may need to filter the information. Create one report parameter for each question that you want the user to answer. Theoretically, you can create a parameter for each piece of data in the data source. To ensure that report parameters are not overwhelming for the user, limit the parameters to important fields.
*When creating more than one report parameter, consider the interaction of the values. For example, if you create two parameters to get the values of state and sales total, decide whether to return rows only if both values in the row match or if either value matches.
*When creating many report parameters, organize them in logical groups. For example, create two groups of parameters to organize customer parameters, such as customer name, city, and state, in one group and order parameters, such as order ID, order date, and order amount, in another group.
*Use short, descriptive text prompts, but ensure the text is not ambiguous. For example, Customer State is clearer than State.
*Do not assume that the user knows how the data is stored in the data source. For example, a user might not know that an order-status field takes three values: Open, Closed, and In Evaluation. Without this knowledge, the user does not know what value to enter for an order‑status parameter. To improve usability, create a drop-down list or radio buttons for the user to select a value instead of requiring the user to type a value. Figure 13‑1 provides an example of a simple, but effective, parameter presentation.