ABAP constants

Summary: in this tutorial, you will learn how to use the ABAP constants keyword to declare constants in the program.

Introduction to ABAP constants

Constants are data objects whose values cannot be changed by the program at runtime using assignments. Their contents are constants.

To declare a constant in the program, you use the constants keyword as follows:

constants constant_name type data_type value intial_value.

In this syntax:

First, specify the constant name after the constants keyword. The name of a constant has at most 30 characters and starts with a letter.
Second, select a data type for the constant after the type keyword.
Third, specify the value of the constant after the value keyword. This is only place where you can specify the constant value.

The following example declares a constant named gc_tax_rate with type f and value 0.07.

constants gc_tax_rate type f value '0.07'.

The following shows how to use the constant gc_tax_rate to calculate the net price:

data gv_price type f value 100.
constants gc_tax_rate type f value '0.07'.

data(net_price) = gv_price * ( 1 - gc_tax_rate ).

To declare multiple constants, you use the chain statement as follows:

constants:
   constant_name_1 type data_type value constant_value_1,
   constant_name_2 type data_type value constant_value_2,
   ...
   constant_name_n type data_type value constant_value_n.

Summary

Use the keyword constants to declare data object whose values does not change in the program.