SAP System Data
Data in the SAP system can be categorized into three types:
- Master Data: Infrequently modified data.
- Transactional Data: Highly volatile data with significant volume generation.
- System or Control Data: Configuration-related data.
System data is stored in database tables.
ABAP Data Dictionary
The ABAP Data Dictionary is the tool in ABAP for managing all data definitions in the SAP system. This includes both standard system definitions and user-created definitions (known as Z). Access the Data Dictionary using transaction SE11.
SE11 Transaction: This ABAP Data Dictionary transaction is extensively used by both ABAP Technical Consultants and Functional Consultants across modules. From this transaction, you can create, modify, and view the following objects:
- Database Tables: ABAP objects for permanent data storage.
- Views: ABAP objects integrating two or more existing database tables, using join and selection conditions.
- Data Types: Types created within the ABAP Data Dictionary for referencing in programs, tables, or configuration. Includes:
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Data Elements: Define the data type of a variable or a field within a database table.
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Structures: Complex data types containing multiple fields.
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Table Types: ABAP data types creating an internal table using a structure format.
- Type Groups: ABAP objects for grouping commonly used data types in programs.
- Domains: ABAP objects specifying the technical details of a database table field.
- Search Helps: ABAP objects defining possible help values for a database table field or a SAP screen field.
- Lock Objects: ABAP objects allowing concurrent updates to database table data, ensuring data consistency.
Note: When an ABAP Data Dictionary object is modified, any ABAP program referencing it automatically adapts to the object's new state upon execution. This is due to ABAP's interpreted nature, eliminating the need to recompile programs referencing modified Data Dictionary objects.
Creating a Database Table, Data Element, and Domain
- Access transaction SE11 and input the new table name to the right of "Database Table" text, then press "Create"
- In the subsequent screen, provide a brief description of the new table under "Short Description"
- In the "Delivery and Maintenance" tab, complete the "Delivery Class" with 'A' (application table with master and transactional data). Other options, like 'C' can be explored by clicking the matchcode button.
- Under "Data Browser/Update" choose "Display/Maintenance Allowed" allowing updates via transaction SM30.
- In the "Fields" tab, define the table's fields. All database tables must have the client as the first field.
- For key fields, tick the ones that shouldn't repeat or have initial or blank values.
- Define field data types: Assign an installed type or create a data element for each field.
- Activate the data element, associating a value range scope: A = Active, I = Inactive, N = Null.
- Configure technical options by pressing the "Technical Settings" button:
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Set "Data Class" to APPL0 for master data transparent tables.
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Define the "Size Category" e.g., 3 for tables with 78,000 to 310,000 records.
- Activate the database table, acknowledging any warning messages. Prioritize viewing the activation log.
- Define the table enhancement category in "Extras/Enhancement Category"
Enhancement Category: Determines if the database table can be extended in the future, allowing additional fields. This concept is closely tied to Append Structures.