DEF VAR hQuery  AS HANDLE   NO-UNDO.
DEF VAR hBuffer AS HANDLE   NO-UNDO.
DEF VAR hFeld   AS HANDLE   NO-UNDO.
DEF VAR cWhere  AS CHAR     NO-UNDO.

DEF VAR iKnr    AS INT      NO-UNDO INIT 5555.

FOR EACH _Field WHERE _Field._Field-Name = 'Knr':

    FIND _File OF _Field.
    CREATE BUFFER hBuffer FOR TABLE _File._File-Name.
    hFeld = hBuffer:BUFFER-FIELD('Firma').

    IF VALID-HANDLE(hFeld) THEN
        cWhere = SUBSTITUTE('FOR EACH &1 WHERE &1.Firma = "1000" AND &1.Knr = &2',
                _File._File-Name, iKnr ).
    ELSE 
        cWhere = SUBSTITUTE('FOR EACH &1 WHERE &1.Knr = &2',
                _File._File-Name, iKnr ).

    CREATE QUERY hQuery.
    hQuery:SET-BUFFERS(hBuffer).
    hQuery:QUERY-PREPARE(cWhere).
    hQuery:QUERY-OPEN().
    
    REPEAT TRANSACTION:
        DO WHILE hQuery:GET-NEXT(EXCLUSIVE-LOCK):
            hBuffer:BUFFER-DELETE().
        END.
        LEAVE.
    END.
                
    DELETE OBJECT hBuffer.
    DELETE OBJECT hQuery.
END.