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ABAP Code Snippet
ARTICLE

No field symbols as a control break criterion
In ABAP Objects it is not allowed to specify field symbols as control break criteria in control level processing.

Error message in ABAP Objects if the following syntax is used:

name = 'WA-COL1'.
ASSIGN (name) TO <(><)>.

LOOP AT itab INTO wa.
AT NEW <(><)>.
...
ENDAT.
ENDLOOP.

Correct syntax:

name = 'COL1'.

LOOP AT itab INTO wa.
AT NEW (name).
...
ENDAT.
ENDLOOP.

Reason:

Control break criteria must be specified with reference to the line structure (columns) of the internal table. Field symbols point to data objects and must not be used for naming structure components. Since dynamic name specification is possible, column specifications via field symbols that point to the used work area are obsolete.