You can choose to display data sets page-by-page rather than in one, long scrollable grid.
If you enable paging, the following bar will appear at the bottom of each page of data.
To turn on paging, open the Designer. Choose the Data Set, then in the Properties, choose General, and select the Support paging check box.
Paging should be turned off if you are using the grouped columns feature because you will only see the groups for the page displayed.