There are challenges when open purchase requisitions (PR) and purchase orders (PO) need to be migrated to SAP system from legacy system. Especially open POs create problem because some part of it may be goods receipt (GR) and some part may be Invoice receipt (IR) done. Now if you migrate these open POs in the SAP system then due to execution of movement type, stock and accounting update will happen (automatic account assignment). So you will end up with 2 entries for each PO (both in legacy system and in SAP system) and your stock balance and account balance will have inconsistencies.
Open PRs need to be migrated because in most cases they are associated with other purchase documents like POs. So if you have open POs and there are referencing PRs then you need to migrate these PRs along with POs. Since PRs do not have accompanying movement types, there will not be any subsequent posting to stocks and accounts. So open PRs do not pose any problem when they are migrated to SAP system. the only consideration is to know which open PRs need to be migrated and which open PRs need to be purged.
When you want to migrate open POs from legacy systems to SAP system then you need to take a lot of care. Here are some strategies:
- If any open POs can be closed in the legacy system then it is better to close them. Later you can migrate those closed POs as archive data.
- If you need to migrate open POs in the SAP system then you need to migrate them in what is akin to offline mode. Here stock and account updates will not happen when they are migrated in SAP.
Let us see the steps involved in migrating open POs into SAP system:
- In IMG you will need to define external number range for POs. Since these POs are coming from a legacy system, the POs should have a number range different from the number range for POs created directly in SAP.
- there is a program RM06EEI0 which is used to upload PO headers. You can use LSMW tool to run this program. The PO header lines will be migrated.
- You will need to upload the file containing Open POs headers to the application server. This file will be a flat file and you will need to make sure that data is cleansed and mapped before saved in this file. Once this file is uploaded then you should check if the file uploaded successfully. Many times, due to large mount of data being uploaded the file may get truncated while uploading and thus only a fraction of data is uploaded. If this is the case then you will need to upload the remaining data again.
- You will check to see if any errors occurred during upload by seeing the error log. You will need to fix those errors.
- For migrating PO line items. you will need to run program RM06EEI1 which is used to upload PO line items. You can use transaction code SA38 to run this program. first you will run this transaction without database update to see if there are no errors. Later you will run this transaction with database update.
- Since actual vendor account and stock update is not to be updated, there are temporary accounts provided which are known as contra account vendor items and contra account goods receipts.
- Once you have uploaded PO line item data successfully then you should again check entries in SAP to make sure that everything is fine.