The ABAP Dictionary is a fully integrated data environment controlling facility. It contains all definitions for Domains, Data Elements, Structures, Tables, Views, Search Helps, Lock Objects, Matchcode Objects, The Table Maintenance Generator, and the Table Description Generator.
With these objects in its repository, the ABAP Dictionary:
- Enforces data integrity
- Manages data definitions without redundancy
- Is tightly integrated with the rest of the ABAP/4 Development Workbench.
Enforcing data integrity is the process of ensuring that data entered into the system is logical, complete, and consistent. When data integrity rules are defined in the ABAP/4 Dictionary, the system automatically prevents the entry of invalid data. Defining the data integrity rules at the dictionary level means they only have to be defined once, rather than in each program that accesses that data.
The following are examples of data lacking integrity:
- A date field with a month value of 13
- An order assigned to a customer number that doesn’t exist
- An order not assigned to a customer
Managing data definitions without redundancy is the process of linking similar information to the same data definition. For example, a customer database is likely to contain a customer’s ID number in several places. The ABAP Dictionary provides the capability of defining the characteristics of a customer ID number in only one place. That central definition then can be used for each instance of a customer ID number.
The ABAP Dictionary’s integration with the rest of the development environment enables ABAP programs to automatically recognize the names and characteristics of dictionary objects.
Additionally, the system provides easy navigation between development objects and dictionary definitions. For example, as a programmer, you can double-click on the name of a dictionary object in your program code, and the system will take you directly to the definition of that object in the ABAP/4 Dictionary.
When a dictionary object is changed, a program that references the changed object will automatically reference the new version the next time the program runs. Because ABAP is interpreted, it is not necessary to recompile programs that reference changed dictionary objects.