Syntax error in MariaDB Stored Procedure With Parameter - mariadb

Question

Im trying to create a procedure for a railway database on phpmyadmin. In which the train number, train date, and category is read from the passenger. On the basis of the values provided by the passenger, corresponding record is retrieved from the Train_Status table. If the desired category is AC, then total number of AC seats and number of booked AC seats are compared in order to find whether ticket can be booked or not. Similarly, it can be checked for the general category. If ticket can be booked, then passenger details are read and stored in the Passenger table.
I have scratched my head on the procdure syntax but it is still giving an error. Tried changing syntax, removing the check condtion from variables but nothing seems to work.
The error it gives is
"#1064 - You have an error in your SQL syntax; check the manual that
corresponds to your MariaDB server version for the right syntax to use
near 'CHECK (train_number>=1 AND train_number<=5); DECLARE t_date
DATE; DECLA...' at line 6"
The mariadb version is 10.4.25
Here it is what I created
DELIMITER $$
CREATE PROCEDURE Booking (t_num int(1), t_date DATE, category varchar(10) )
BEGIN
DECLARE t_num int(1) CHECK (train_number>=1 AND train_number<=5);
DECLARE t_date DATE;
DECLARE category ENUM('AC', 'General');
DECLARE status ENUM('Confirmed', 'Waiting');
DECLARE getTrain CURSOR FOR
SELECT * FROM Train_Status
WHERE train_number = t_num AND train_date = t_date;
DECLARE trec Train_Status % ROWTYPE;
DBMS_OUTPUT.PUT_LINE('READING VALUES');
t_num := &t_num;
t_date := '&t_date';
category := '&category';
OPEN getTrain;
LOOP
FETCH FROM getTrain INTO trec;
EXIT WHEN getTrain % NOTFOUND;
IF(category = 'AC') THEN
IF(trec.t_acseats - trec.b_acseats) > 0 THEN
status := 'Confirmed';
DBMS_OUTPUT.PUT_LINE('Seat Confirmed');
ELSIF(trec.t_acseats - trec.b_acseats) > -2 THEN
status := 'Waiting';
DBMS_OUTPUT.PUT_LINE('Seat Waiting');
ELSE
DBMS_OUTPUT.PUT_LINE('Seat Not Available');
EXIT;
END IF;
IF status = 'Confirmed' OR status = 'Waiting' THEN
UPDATE Train_Status SET b_acseats = b_acseats + 1 WHERE
TrainNumber = t_num and TrainDate = t_date;
END IF;
ELSIF(category = 'General') THEN
IF(trec.t_genseats - trec.b_genseats) > 0 THEN
status := 'Confirmed';
DBMS_OUTPUT.PUT_LINE('Seat Confirmed');
ELSIF(trec.t_genseats - trec.b_genseats) > -2 THEN
status := 'Waiting';
DBMS_OUTPUT.PUT_LINE('Seat Waiting');
ELSE
DBMS_OUTPUT.PUT_LINE('Seat Not Available');
EXIT;
END IF;
IF status = 'Confirmed' OR status = 'Waiting' THEN
UPDATE Train_Status SET b_genseats = b_genseats + 1
WHERE TrainNumber = t_num and TrainDate = t_date;
END IF;
ELSE
DBMS_OUTPUT.PUT_LINE('Invalid Category');
END IF;
IF status = 'Confirmed' OR status = 'Waiting' THEN
INSERT INTO Passengers
VALUES ('&T_ID', t_num, t_date, '&Name', &Age, '&Sex', '&Address', status, category);
END IF;
END LOOP;
CLOSE getTrain;
END $$
DELIMITER ;

Answer 1

Check can't be used while declaring the variables. Only name and data type should be there.
Check cursor syntax from MariaDB documentation.
These two things will solve your 70% problems. Rest you can figure out.