IF TO_CHAR(v_dateadd, 'DAY') = 'СУББОТА' THEN
            v_dateadd := v_dateadd + 1;
        END IF; 

CREATE OR REPLACE PROCEDURE schedule_tr
(p_training_id IN NUMBER,
 p_username IN VARCHAR2,
 p_training_date IN DATE) IS
 
rec schedule%ROWTYPE;
v_dateadd schedule.training_date%TYPE := p_training_date;
cnt NUMBER := 0;
BEGIN 
SELECT *
INTO rec
FROM schedule
WHERE training_id = p_training_id 
AND training_date = p_training_date;

IF rec.username = p_username  THEN
    DBMS_OUTPUT.PUT_LINE('The schedule for this user already exists on this date!');
ELSIF rec.username != p_username THEN 
    DBMS_OUTPUT.PUT_LINE('This ID is already in use!');
ELSE 
    LOOP
        IF TO_CHAR(v_dateadd, 'DAY') = 'ВОСКРЕСЕНЬЕ' THEN
            v_dateadd := v_dateadd + 1;
        END IF;
        
        INSERT INTO schedule(training_id,username, training_date)
            VALUES(p_training_id, p_username, v_dateadd);
            
        IF TO_CHAR(v_dateadd, 'DAY') = 'СУББОТА' THEN
            v_dateadd := v_dateadd + 1;
        END IF;
        
        v_dateadd := v_dateadd + 2;
        cnt := cnt + 1;
        EXIT WHEN cnt = 12;
    END LOOP;
END IF;

EXCEPTION WHEN NO_DATA_FOUND THEN
    LOOP
        IF TO_CHAR(v_dateadd, 'DAY') = 'ВОСКРЕСЕНЬЕ' THEN
            v_dateadd := v_dateadd + 1;
        END IF;
        
        INSERT INTO schedule(training_id,username, training_date)
            VALUES(p_training_id, p_username, v_dateadd);
            
        IF TO_CHAR(v_dateadd, 'DAY') = 'СУББОТА' THEN
            v_dateadd := v_dateadd + 1;
        END IF;
        
        v_dateadd := v_dateadd + 2;
        cnt := cnt + 1;
        EXIT WHEN cnt = 12;
    END LOOP;
END schedule_tr;