If you data source can be a view or stored proc to limit the records to the last 6 months then no problem. just add the paramter as indicated below.

 

If not I am not sure you will be able to get exaclty what you want. When you add this parameter the user will be selecting from ALL order #s in the table, not just ones in the last 6 months.

 

Either way you will need to create a parameter, make it dynamic, link the value to the Order # and set the options to allow for multiple values as TRUE.

Change your select statement to

{Table.order#}={?my parameter}.

This will set the prompt for the selection and populate the list to select from.

 

On the same point I have found that if I use the 'dynamic list' option and point my parameter to a table in my report (not an outside list), it seems to have a limit in how many records it displays.  Is that normal?  Does anyone know of the maximum number of records it will display?   For that reason I cannot use the dynamic option if I am choosing from a database that has thousands of records in my 'dynamic list' table.

This might be a factor for you if my conclusion is correct.

Regards

 

In Crystal XI Dynamic parameter returns only 1000 LOV values which can be viewed at a time.

Default number set for LOV in Crystal Reports XI R2

Resolution

Crystal Reports XI Release 2

Create a registry key HKEY_LOCAL_MACHINE\SOFTWARE\Business Objects\Suite 11.5\Crystal Reports\DatabaseOptions\LOV.

NOTE
Alternatively, you can create the registry key HKEY_CURRENT_USER\SOFTWARE\Business Objects\Suite 11.5\Crystal Reports\DatabaseOptions\LOV and that key will override the settings of the HKEY_LOCAL_MACHINE\SOFTWARE\Business Objects\Suite 11.5\Crystal Reports\DatabaseOptions\LOV key.

Add a string value "MaxRowsetRecords" and set the value to the maximum number of values that you desire for your report. For example, a value of 2000 will return up to 2000 values in the lowest level of a cascading parameter

Cheers

Rahul