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ABAP Keyword Documentation →  ABAP Programming Guidelines →  ABAP-Specific Rules →  Programm Type and Program Properties 

Program Attributes

Other versions: 7.31 | 7.40 | 7.54


Alongside various, less important properties, each ABAP program has a set of program attributes that control specific aspects of the program behavior and syntax check severity:

  • Fixed point arithmetic
    For respecting the decimal separator for operations with packed numbers.
  • Logical database
    For connecting an executable program with a logical database.

The program attributes are defined when a program is created the relevant tool (Class Builder, Function Builder, ABAP Editor). It is possible to change them later.


Use the default settings for program attributes

Set the program attributes for new programs as follows:

  • Unicode Checks Active activated
  • Fixed Point Arithmetic activated
  • No assignment to a logical database

When a new program is created, these settings are the same as the default values. This means that they can be applied without making any changes. Once the program attributes are set they should no longer be modified.


Different behaviors or check severities are only provided for compatibility reasons, to ensure that existing programs can still be compiled and executed. New programs should definitely not use obsolete settings.

  • When a new program is created, the Unicode Checks Active attribute is already set by default. This attribute must never be reset. Activating the Unicode checks is the only way to ensure that the program can be executed in Unicode systems and in non-Unicode systems, and that the same results are returned in both cases. A program with activated Unicode checks is referred to as a Unicode program. A Unicode system represents an SAP system, where characters are displayed in Unicode format (ISO/IEC 10646). (Currently UTF-16 with platform-dependent byte order. Here, the ABAP programming language supports the subset covered by UCS-2.) In a Unicode system, only execute Unicode programs can be executed. However, Unicode programs can also be executed in non-Unicode systems. The programs provided by SAP are usually Unicode programs. When a non-Unicode system is prepared for the switch to Unicode, all existing non-Unicode programs must be implemented as Unicode programs. Activating the Unicode checks is only beneficial for the developer (for example, a more stringent static type check and a stricter separation of byte and character string processing).
  • When a new program is created, the Fixed Point Arithmetic attribute is already set by default. This attribute must never be reset. If fixed point arithmetic is disabled, the position of the decimal separator of packed numbers (type p) is only respected for output in a classic dynpro, in assignments to fields of the types c and string, or for formatting using WRITE TO. The position is not respected for calculations. Today, this behavior only rarely meets the developer’s expectations. If the calculation is to be carried out with packed numbers without any decimal places, this must be specified using the DECIMALS 0 addition for the declaration.
  • When a new executable program is created, the Logical Database attribute is empty. This attribute assigns executable programs to a logical database. This enables the selection screen and flow of the program to be combined with the selection screen and flow of the logical database. A logical database is a special development object that is edited in Logical Database Builder and which provides other ABAP programs with data from the nodes of a hierarchical tree structure. A logical database has a hierarchical structure, an ABAP database program and a separate standard selection screen. Logical databases should no longer be used. This is because they are based on cross-program usage of global data, implicit subroutine calls and reporting event control, and therefore do not comply with modern concepts. The function module LDB_PROCESS can be used to access existing logical databases. This function module can be called from a method. No new logical databases should be created. Instead a relevant service should be made available using a global class.

Because any later changes to the program attributes potentially involve extra work, the correct attributes should be configured right from the start and not changed later. It is particularly important for attributes that influence the syntax check (currently the Unicode check) that the highest possible check severity is chosen. This ensures the best preparation for any subsequent switches.

The following sections assume that only the Unicode check is used and fixed point arithmetic is activated and that logical databases are not used. These guidelines no longer contain a special rule for obsolete or problematic language constructs, which are only available if the Unicode checks are switched off. These constructs are only mentioned briefly in regard to the list of obsolete language elements.


From Release 740, SP05, the strict modes in the Open SQL syntax check demand Unicode programs in which the program attribute fixed point arithmetic is switched on.


In the following source code performs a substring write across two numeric components of a structure.

    BEGIN OF struct,
      comp1 TYPE i,
      comp2 TYPE i,
    END OF struct.
  struct+2(4) = 'XXXX'.

This is only possible in non-Unicode programs. Here an implicit casting of the subarea is performed for type c. The result in the components depends on the alignment gaps, the internal presentation of numeric values (byte order), and the code page used. Therefore, the result is extremely platform-dependent. A live program must never contain this type of code. This type of code often results in incorrect data or runtime errors that are difficult to trace.

The above code results in a syntax error, when used in an ABAP program where the Unicode Checks Active attribute is selected in the program properties (in accordance with the above rule). Unwanted substring accesses are prohibited, just like any other unwanted accesses to structures or other parts of the working memory. If these accesses cannot be identified by the syntax check, a runtime error occurs with a descriptive short dump while the program is running.