As you might imagine, any business that starts using a system like SAP will most likely want to transfer data from their old system. This might be anything from customer details, to open invoices on customer/supplier accounts, to closing ledger balances. Transferring can be done two ways, manually to using an interface.
Ultimately, using an interface is probably best as it automates mundane work and is likely to be less error prone than manual entry. For example, can you imagine and organisation with 2,000 customers, each with 5 outstanding invoices? That’s 10,000 entries to be made manually – not an ideal scenario. So an interface would be the best option, but what is an interface?
In this case, we can describe an interface as an agreed format to transfer data from one system to another. SAP for example uses a concept call iDocs to not only transfer data within SAP, but also receive data from outside. You can think of an iDoc as a simple text file, with lines of text. The first line is a control record, with each line thereafter a data record. In simple terms, the control record tells the system where the data which follows is to go. Each record (line) in the iDoc is 1,000 characters long, and the position of each character determines what the data means – the positions are defined by SAP. Here is an example of what an iDoc record might look like:
ORDERHEADER 1088 1089 12500.50 24121998 Micky Mouse
Normally, a programmer develops some programme code which can extract data from the sending system to comply with iDoc format. Then, when the programme is run, the iDoc is read by SAP and the relevant data fields are populated e.g. customer details, open invoices.