When the report is refreshed with dynamic parameters, the list of values are not shown.
Reproducing the Issue
- Create a report based on a command object.
- Add a parameter at command object level.
- Run the report. In field explorer this parameter appears as a static parameter.
- Edit the parameter and convert it to Dynamic parameter based on a suitable field.
- Save the parameter and report.
- Refresh it to check the parameter prompt.
The purpose of dynamic parameter is to get the latest list of values from the database (at runtime). When a dynamic parameter is created in a report, it generates a prompt group which contains the list of values.
For Dynamic parameters:
When the report is refreshed the request is sent to the database to get the latest values to generate list of values. With these list of values, the crystal engine generates a prompt which is shown to user. User provides the values to the prompt and based on these values, an SQL is generated to fire on database.
For Static parameters:
When report contains static parameters the list of values (if created) are stored with the report itself. Also while refreshing the report, there is no need to request the database for latest list of values. So when the report is refreshed, the static prompt is shown and depending upon the provided values, the SQL is fired on the database.
In this particular case:
The parameter is created at command object level. At this level it is not possible to show the list of values because there is no separate request for fetching the list of values.
At this level, the parameter cannot get the list of values even if we try to edit it in the report and try to append the values related to any database field.
So when it is converted to dynamic and crystal tried to create a prompt group it never finds any list of values. The prompt is created with some fault. We can observe this when we refresh the report with dynamic parameters we can not see the list of values.
Write the commands without any parameters. Create the dynamic parameter in the report itself and use it in record selection formula to filter the data which is fetched by command.
If the users are not interested in list of values then the same command object with static parameter can be used.
KBA , BI-RA-CR , Crystal Reports designer or Business View Manager , Problem