DDS externally describes the format of data so that individual programs do not have to contain similiar definitions. This detailed description is associated with the data itself and exists outside the programs that use it. The application programmer does not define the information format in the source program. Information is extracted from the DDS language description and is incorporated into the program just as if it were coded in the source program. The DDS definitions will be brought into the program at compile time.
Because of the DDS file structure, the amount of data you must define and store is reduced. In addition, once applications are added or modified, the system immediately makes the changes available so that your programs use the latest information without affecting existing programs.
Advantages to using externally described data:
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