A purchasing document is an instrument used by Purchasing to procure materials or services.
The following list shows the various external purchasing documents available in the standard SAP System. (Note: purchase requisitions are not included on this list because they are usually regarded as internal documents used within Purchasing and are therefore treated separately.)
Request for quotation (RFQ)
Transmits a requirement defined in a requisition for a material or service to potential vendors.
Contains a vendor's prices and conditions and is the basis for vendor selection.
Purchase order (PO)
The buying entity’s request or instruction to a vendor (external supplier) to supply certain materials or render/perform certain services/works, formalizing a purchase transaction.
In the SAP Purchasing component, a type of "outline agreement", or longer-term buying arrangement. The contract is a binding commitment to procure a certain material or service from a vendor over a certain period of time.
Another type of "outline agreement", or longer-term buying arrangement. Scheduling agreements provide for the creation of delivery schedules specifying purchase quantities, delivery dates, and possibly also precise times of delivery over a predefined period.
Requirements of materials or services can be reported to Purchasing by means of purchase requisitions.
Each purchasing document is subdivided into two main areas: the header and individual items. Each document will contain a header and can contain several items.
The header contains information relevant to the whole document. The items specify the materials or services to be procured. For example, information about the vendor and the document number is contained in the document header, and the material description and the order quantity are specified in each item.
The additional data provides extra information about the item, and has no direct connection with the item procurement data. Additional data includes, for example, account assignment data (such as cost center and G/L account) and the PO history for an item, which contains information on already recorded goods and invoice receipts relating to the item.
Each item in a purchasing document represents a unit of procurement. Purchasing operations (involving requisitioning, ordering and follow-up processes) occur on an item-specific basis.
How does the SAP System Differentiate Between Purchasing Documents?
In the SAP System, the different kinds of purchasing document are distinguished from one another by means of the document type. The latter determines the relevant number range and the fields that are offered to you for data maintenance purposes, for example. The relevant document type appears as a default value when you create a purchasing document.
Document types are defined for RFQs, purchase orders, and contracts, for example. The standard SAP system includes certain document types. However, your enterprise can also define its own.
How are Purchasing Documents Numbered?
Each document is assigned a unique number. (Note that the "number" may also be an alphanumeric code: see below). This number can be assigned internally or externally, depending on the policy of your enterprise. Internal number assignment means that the system assigns the number. External number assignment means that the person creating the document must supply it.
Alphanumeric assignment is only possible in the latter case.