Replace Empty values with drop down list in datatable

I have a data table with following column.What I want it to display a drop down list if "businessUnit" or "System" column value is empty otherwise it will display the plain text.

"aoColumns": [ { "sTitle": "Business Unit","mDataProp": "businessUnit" }, { "sTitle": "System", "mDataProp": "system" }, { "sTitle": "ReviewGroupName", "mDataProp": "reviewGroup"} ]