Modifying the Standard 

Before you modify your system or develop your own solution, make sure that your requirements cannot be fulfilled by either Customizing or Personalization, or by the exits or business add-ins provided in the system.

Before making modifications to the standard, refer to the section on the Modification Assistant.

For information on modifying SAP tables, consult the portion of the ABAP Dictionary documentation called Making Changes to Tables. You can also create append structures for tables and structures with the Modification Assistant (see Modifying Tables and Structures).

SSCR (SAP Software Change Registration) is a procedure for registering all modifications to SAP source code and SAP Dictionary objects. For more information on this subject, see the section on the SAP Software Change Registration Procedure (SSCR).

You should also consult the sections General development organization and Notes on modifying the standard before modifying the standard.