User`s guide
2.
In the Field Explorer, select Parameter Fields and click New.
The Create New Parameter dialog box appears.
3.
Enter a name for the parameter in the Name field.
This example uses Customer Name.
4.
In the List of Values area, click Dynamic.
5.
Click Insert and, in the Value field, select Customer ID.
6.
In the Description field, select Customer Name.
7.
In the Value Options area, set the Prompt with Description Only option to True.
8.
Click OK.
When your users see this prompt in the prompting dialog box, they do not see values from the Customer
ID field (the field on which the parameter is based), but rather, they see a list of customer names.
21.8.3 Using command objects as list-of-values data sources
Crystal Reports supports command objects as data sources for unmanaged lists of values. To use this
feature, you first create a command object using the Database Expert to return the values that you want
in your list-of-values object.
For more information see "Defining an SQL Command" in the online help.
The query you create should return at least one database field per level in the new list-of-values object.
For example, if you want to build a Country, Region, City list-of-values object, your query should return
at least three columns from your database: Country, Region, and City. You need to return all three
values in a single select statement. There is no need for an order by clause, because the prompting
engine sorts the values according to your specifications.
Note:
It is not necessary to link your command object to your report fields. In general, command objects that
you use only to populate lists of values do not need to be linked to your report. However, if you want
to use a column from this command object in your report, you need to link the command object to the
report.
All the command objects defined in your report appear in the value fields drop-down list, and in the
description fields drop-down list in the Create New Parameter dialog box. You can then associate your
list of values with the command object.
21.8.4 Null handling
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Parameter Fields and Prompts