BIRT provides the capability to use dynamic parameters to present the end user with a list of choices that are populated from a dataset. This is very useful but can cause issues when the dataset returns many rows of data. To reduce the number of items in any parameter, the developer can use a cascaded parameter, which allows multiple levels and multiple datasets. When the user selects the first level parameter in a cascaded parameter group the second level in the group is automatically re-queried…….
Source : BIRT Cascaded Parameters