Processing Posted Data
You control processing of entered data with theposting key in that you specify whether the transaction is a payment transaction, and what posting key is used to reverse the document.
Customer and vendor account line items that are created by a payment must be properly indicated. This information is required for analyzing payment history and creating payment notices.
In the FI-GL, FI-AR, and FI-AP components, a reverse posting is automatically created if you reverse a document. To do this, the system requires a reverse posting key, which you specify for each posting key. The system determines the reverse posting key by referring to the posting key used in the document to be reversed.