To enable you to view and edit formatted IMS data in the IMS Database Editor, you first use the IMS Segment Layout Editor to define the formatting for the data in IMS segments. The layout describes the name, length, and picture of each field in the segment.
You can create one or more segment layout files for each IMS database, depending on how many COBOL programs access that database. Each segment layout file can contain one or more segment layouts, based on the data structures contained in the Data Division of a COBOL program that accesses the database - one program per segment layout file.
The Segment Layout Editor extracts the data structure from the Data Division of a COBOL program by reading its debug information (.idy) file, which is generated by Enterprise Developer when you compile the program. For each layout definition, you attach a data field or structure to an IMS segment.
Once the segment layouts are defined, use the IMS Database Editor to apply the segment layout formatting.