SQL游标输出“过程成功完成”而不是设置消息

Question

CREATE OR REPLACE PROCEDURE check_reviewer (vc_username VARCHAR2, vc_password VARCHAR2) IS
    CURSOR cur_reviewer IS
    SELECT username, password, reviewer_id
    FROM reviewers
    WHERE username = vc_username AND password = vc_password;
    vn_reviews NUMBER;
BEGIN 
    FOR rec_cur_reviewer IN cur_reviewer LOOP
        IF rec_cur_reviewer.username = vc_username
            AND rec_cur_reviewer.password = vc_password
        THEN
            vn_reviews := func_reviews_from_reviewers(rec_cur_reviewer.reviewer_id);
            DBMS_OUTPUT.PUT_LINE('Amount of reviews for reviewer ' || rec_cur_reviewer.reviewer_id || ' is: ' ||vn_reviews);
        ELSE 
            DBMS_OUTPUT.PUT_LINE('NO REVIEWS');
        END IF;
    END LOOP;
EXCEPTION 
    WHEN OTHERS THEN 
        DBMS_OUTPUT.PUT_LINE(SQLERRM);
END check_reviewer;
/

它输出“过程成功完成”而不是DBMS消息。我已经尝试设置serveroutput已经无济于事。