Once we had the list from the legacy system in excel we used trx LSMW upload to assign health centre, create service and assign the protocol on OH with trx EHSAMTAET. We did not go through the OH planning cockpit for the uploads.
The good thing with the LSMW is that the dependant tables (plenty of them) are also updated which can be very tricky if you try to directly create the file.
To export, if you have access to trx SE16 on ECC client (mostly dont) then just export the fields directly from the table - always service number and pernr (mappernr) and personID to establish a link back to the legacy data in excel or whatever format you have.
Else use trx SQVi to create a query on the two tables to export the detail.
Once you have the personID as mapped to the Service number you can upload with LSMW.
The trick is to group your legacy data so that you can match the screens and not do multiple services or protocols on one load (so that your selection in the LSMW follows the same for all the data). The trx EHSAMBTAET in the LSMW recording is difficult.
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