The Data Structure entity
Data Structures describe all the data sets that are processed by the applications. These data sets are represented by Segments or Tables.
A data Structure groups the Segments in a logical way. Segments can represent elements such as:
- Records of files
- Work areas of Programs
- Segments of databases
A Data Structure is described logically, with no physical characteristics.
This description can then be reused for different purposes:
Example: A Segment can be used in a database
and in the Programs that access the database.
Information of a physical nature (such as organization or block size) is added when the Data Structure is used in Programs or Database Blocks.