HELP

CREATE OR REPLACE FUNCTION f3(datum IN DATE) RETURN NUMBER AS

check_this_date DATE := datum;
NAME_des_BUCHES VARCHAR2(255) := '';
num_bernd NUMBER := 0;

CURSOR c1 IS SELECT COUNT(*) count_youre_books, KUNDE.AUSWEISNR, kunde.Vorname, AUSLEIHE.barcode_id, AUSLEIHE.ENTLEIHENDE FROM kunde, ausleihe WHERE AUSLEIHE.ENTLEIHENDE < check_this_date GROUP BY AUSLEIHE.barcode_id;

c2 c1%ROWTYPE;

BEGIN
OPEN c1;
LOOP

    FETCH c1 INTO c2;
    EXIT WHEN c1%notfound;

    num_bernd := c2.count_youre_books;
    EXECUTE IMMEDIATE 'SELECT BUCH.TITEL from buch, buch_kopien WHERE buch_kopien.barcode_id = ' || c2.barcode_id || ' AND buch.isbn = buch_kopien.isbn' INTO NAME_des_BUCHES;

    DBMS_OUTPUT.put_line('K_ID: ' || c2.AUSWEISNR || ', Vorname: ' || c2.vorname || ', Buch: ' || NAME_des_BUCHES);

END LOOP;
CLOSE c1;
END;

DECLARE
datum DATE := SYSDATE;
zahl NUMBER := 0;
BEGIN
zahl := f3(datum);
END;