If you recently upgraded to Mono 4.0 and you use DataTables to return SQL results (in my case from Postgresql), you may have received a heart attack similar to mine when you were bombarded with the error:
SourceTable is required to be a non-empty string
This appears to be related to Bug #29557: https://bugzilla.xamarin.com/show_bug.cgi?id=29557
Thought .Net is perfectly happy allow
DataTable whatever = new DataTable();
Mono will throw an exception.
It is looking for you to name the data table.
To fix, simply change
DataTable whatever = new DataTable();
to
DataTable whatever = new DataTable("some_name");
Happy compiling!