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Start Values

Other versions: 7.31 | 7.40 | 7.54

Background

If you declare a data object with the DATA statement, you can use the VALUE addition to set a value, with which the data object is filled when it is created. If the VALUE addition is not used, the system uses the type-specific initial value. If the CONSTANTS statement is used, the VALUE addition must always be specified. If the type-compliant initial value is required here, this can be achieved using the addition VALUE IS INITIAL.

If the specified start value does match the type and length of the data object, the value is converted when the program is generated.

Rule

Start values must match the data type of the data object

Only use the addition VALUE to enter start values that exactly match the data type of the declared data object in terms of type, content, and length.

Details

The start value cannot always be specified to conform with the type, since ABAP does not support type-compliant literals for all possible data types. In all cases where a conversion cannot be avoided, choose the content of literals specified as start values so that the actual value meets the requirements when the source code is read.

Bad example

The average reader may well expect the constant high_noon in the following source code to contain the value 120000. However, the constant actually contains the value 092000, because the value of the numerical literal refers to the number of seconds. This means 12,000 seconds is actually the time 09:20 on the following day.

CONSTANTS high_noon TYPE t VALUE 120000.

Good example

The following source code corrects the above example by replacing the number literal with a text field literal. Now the constant high_noon contains the expected value 120000.

CONSTANTS high_noon TYPE t VALUE '120000'.