ABAP programming

When you run an ABAP program, you call its processing blocks. ABAP programs are controlled
from outside the program itself by the processors in the current work process.



Type I
Type I programs - called includes - are a means of dividing up program code into smaller, more
manageable units. You can insert the coding of an include program at any point in another ABAP
program using the INCLUDE statement. There is no technical relationship between include
programs and processing blocks. Includes are more suitable for logical programming units, such
as data declarations, or sets of similar processing blocks. The ABAP Workbench has a
mechanism for automatically dividing up module pools and function groups into include
programs.



SY is a structure with the ABAP Dictionary data type SYST. The components of SY are known as
system fields. System fields contain values that provide information about the current state of the
system. They are automatically filled and updated by the ABAP runtime environment. Examples
of system fields:
SY-SUBRC: Return code for ABAP statements
(zero if a statement is executed successfully)
SY-UNAME: logon name of the user
SY-REPID: Current ABAP program
SY-TCODE: current transaction
SY-INDEX: Number of the current loop pass

LIKE
can be used in the same ABAP statements as the TYPE addition to refer to any data
object that is already visible at that point in the program. The expression is either
the name of the data object or the expression

Definition of local types in a program using
TYPES LIKE .
The new data type inherits all of the technical attributes of the data object .