Data Dictionary

• Data Dictionary central data repository system and it is nothing but Data Base.
• Transaction Code: SE11.
• The ABAP/4 Dictionary describes the logical structure of the objects used in application development and shows how they are mapped to the underlying relational database in tables or views.
• Tables, Structures and Views are the three most important objects of ABAP/4 Dictionary. Tables are defined independently of the database. Once these objects are defined and activated they are available to all system components thus ensuring data integrity, data consistency and data security.

• ABAP/4 Dictionary is completely integrated with the ABAP/4 Development workbench.
• The basic objects for defining data in the ABAP/4 Dictionary are tables, domains and data elements. Domains are used for the technical definition (for example field type, field length) of a table field, and data elements for the semantic definition (for example, short description).
• Components of Data Dictionary.

1. Tables
2. Views
3. Data Types
4. Type Group
5. Domain
6. Search Help
7. Lock Objects

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