Hi,
your are loading the data form 2 source to 1 DSO - you need to crate the 2 DTP and 2 transformations to DSO. or you want load the 2 source data one time to DSO you need to write the start or end routine ABAP program but you need to check 2 or 3 common fields should be match.
if not understand the ABAP logic fallow the first process.
DSO before activation new data table data contain after activation data will move to active data table- it will act sequential loading.
same time it is not possible.
Thanks,
Phani.