Generate a column with unique ID

This property is set by default. It allows Business Analytics to add a field to each List item and assign a unique ID to each. This ensures that duplicate item IDs, if any, from the various SharePoint Lists you are merging are not a problem.

If merging more than one SharePoint task list, generate a column with unique predecessor?

This property is only required if there is more than one input block with results from a SharePoint Task List.

For task lists, each task has a predecessor indicating task dependencies. Merging task lists can result in predecessors being erroneously merged as the predecessors are not unique.

To fix this problem, you must set this option and then select the field that identifies task predecessor for each input block with task list results.

Select which field is the predecessor for each input block

These properties are only available if you have set the option to generate unique predecessors. One property is available for each input block you are merging.

For those input blocks whose results are task lists, select the field in the results to identifies task predecessors (dependencies). Business Analytics will add a column with unique predecessor information for the merged list and use the predecessor information for each input block to properly assign dependencies.