Numbering in RAP ABAP

Table of Contents

Numbering in ABAP RESTful Application Programming (RAP) refers to the automatic generation of unique identifiers (numbers) for business object instances. This is crucial for creating keys for entities like sales orders, invoices, or any master data records.

Key Concepts

✔ Automatic vs. Manual Numbering
✔ Number Range Objects (Traditional Approach)
✔ UUIDs (Alternative for Cloud)
✔ Draft Handling Considerations

1. Numbering Strategies in RAP

A. Managed Numbering (Automatic)

When using managed business objects, RAP can automatically handle numbering:

define behavior for ZI_SalesOrder
{
  create;
  
  // Field control - number is assigned automatically
  field ( readonly ) SalesOrderID; 
}

Characteristics:

SAP automatically assigns numbers
Requires proper annotation in CDS view
Simplest approach for new developments

B. Unmanaged Numbering (Custom Logic)

For full control, implement in behavior class:

CLASS zcl_order_behavior DEFINITION.
  PUBLIC SECTION.
    METHODS:
      create FOR MODIFY
        IMPORTING entities FOR CREATE SalesOrder.
ENDCLASS.

CLASS zcl_order_behavior IMPLEMENTATION.
  METHOD create.
    " Custom numbering logic here
    DATA(lv_next_number) = get_next_number_from_range().
    
    LOOP AT entities ASSIGNING FIELD-SYMBOL(<fs_entity>).
      <fs_entity>-SalesOrderID = lv_next_number.
      lv_next_number = lv_next_number + 1.
    ENDLOOP.
  ENDMETHOD.
ENDCLASS.

2. Implementation Approaches

A. Using Classic Number Range Objects

Create number range in transaction SNRO
Implement in behavior class:

METHOD get_next_number_from_range.
  CALL FUNCTION 'NUMBER_GET_NEXT'
    EXPORTING
      nr_range_nr = '01'
      object      = 'ZORDER'
    IMPORTING
      number      = rv_number.
ENDMETHOD.

B. Using UUIDs (Cloud-Friendly)

For cloud/SAP BTP applications:

@ObjectModel: { 
  createEnabled: true,
  deleteEnabled: true,
  updateEnabled: true,
  uuid: #AUTO
}
define view entity ZI_Order...

Advantages:

No number range maintenance
Globally unique identifiers
Better for distributed systems

C. Hybrid Approach

Combine both methods:

METHOD generate_id.
  IF is_cloud_system = abap_true.
    rv_id = cl_system_uuid=>create_uuid_x16_static( ).
  ELSE.
    " Use classic number range
  ENDIF.
ENDMETHOD.

Comparison Between Managed and Unmanaged

Method	Pros	Cons	Best For
Managed	Simple, no coding	Limited control	Simple apps
Unmanaged	Full control	More development	Complex scenarios
Number Ranges	Sequential, readable	Maintenance needed	On-premise
UUIDs	No conflicts, cloud-ready	Not human-friendly	Cloud/SAP BTP

Conclusion

Numbering in RAP can be implemented through various approaches depending on requirements:

Managed numbering for simple cases
Custom implementation for complex scenarios
Number ranges for traditional systems
UUIDs for cloud applications