Understanding the IDoc schema

The RSEIDOC3 report is composed of a packet container that can hold one or more IDocs. Therefore, the schema generated represents the contents. Each IDoc contains a control record, many data records, and some status records. Each IDoc consists of, and its sequence and structure are dictated by, the sequence and structure of segments in a particular kind of IDoc.

The IDoc structure is either ALE or EDI and schemas are generated for each format appropriately.

• The ALE format is designed specifically for use with SAP's Application Linking and Enabling architecture. Each schema generated is compatible with ALE/RFC communications. It requires that each data segment in an IDoc be of the same length with no terminators and the control segment be of fixed length. Each segment is padded to a fixed length.
• The EDI format is loosely modeled after Electronic Data Interchange standards. Each schema generated is compatible with EDI/FILE-based communications. Each segment is variable-length and line-character-terminated.

The attributes of a schema correlate directly to the IDoc metadata report. The IDoc fields correspond to items in a type. For example, the field name generates the item name and the text generates the item description. IDoc data is character-based and only the text or item description is language-dependent.

The schemas generated for either ALE or EDI contain types that are identically defined named Packet, IDoc, Group_number, Field, and Control Record. However, there are differences in how the segments are defined for the two different formats. A schema generated for ALE does not contain a Status Record type.