SQL PROCEDURE ISSUE,not sure on placement of data - mysql

Question

Write a stored procedure that updates the weekly duty roster for an employee and allocates him/her a maximum of 5 work shifts in a given branch. To update the roster, the procedure ensures that:
i. The employee has an existing roster allocated to her/him. In case there is no existing roster for a given employee, the procedure doesn’t update the roster, rather prints an appropriate error message.
ii. The day of current roster is shifted by one day in the updated roster. For instance, if the current roster for an employee shows work shifts from Monday to Friday, then the updated roster will allocate work shifts from Tuesday to Saturday. For simplicity, we will assume that the type and number of work shifts allocated to an employee remain
same from week to week unless an exception occurs such as overallocation. However, the manager may wish to add any extra work shifts to an employee manually.
iii. A warning message is displayed in case the allocated hours of work for an employee exceeds the standard hours of work (35 hours per week).
any help is appreciated having a lot of trouble getting this right.. MYSQL
DELIMITER //
DROP PROCEDURE IF EXISTS updateRoster
CREATE PROCEDURE UpdateWeeklyRoster (IN e CHAR(8), IN b INT)
BEGIN
-- variable declaration
DECLARE WORKING_HOURS INT(35);
DECLARE Updated_Working_Shift_ID INT;
-- cursor declaration
DECLARE c1 CURSOR FOR
EmployeeID,BranchID,WorkingShiftID;
DECLARE CONTINUE HANDLER FOR NOT FOUND set finished = 1;
-- check whether the employee exists or not
SELECT EmployeeID into e
FROM DutyRoster
WHERE EmployeeID = e;
IF e IS NULL THEN
SIGNAL SQLSTATE '45000' set MESSAGE_TEXT = 'THERE IS EXISTING ROSTER';
ELSE
-- actual part
-- delete existing tuples relevant to the given employee and branch id from the Duty Roster table
OPEN c1;
-- execute a loop
REPEAT
FETCH c1 into .... , ....., .....;
-- find the workingShiftWeekDay: assign appropriate values into Current_Week_Day
-- Find the Updated_Week_Day
SET Updated_Week_Day =
CASE Current_Week_Day
WHEN Week_day='MONDAY' THEN Updated_Week_Day='TUESDAY';
WHEN 'TUESDAY' THEN 'WEDNESDAY';
WHEN 'THURSDAY' THEN 'FRIDAY';
WHEN 'FRIDAY' THEN 'SATURDAY';
WHEN 'SATURDAY' THEN 'SUNDAY';
WHEN 'SUNDAY' THEN 'MONDAY';
ELSE .....
END CASE;
-- Find the current_duty_type
-- for the updated_week_day, find an appropriate working shift id
SELECT dutyType into WorkingShiftID
FROM WorkingShift
WHERE EmployeeID AND dutyType = CurrentDutyType;
-- insert the new record
INSERT INTO DutyRoster VALUES (e,b,Updated_Working_Shift_ID);
UNTIL ........;
END REPEAT;
CLOSE c1;
-- Checking whether an employee works for more than 35 hours
SELECT HOUR(TIMEDIFF(WorkingShiftEndTime,WorkingShiftStartTime)) INTO TOTAL, WORKING_HOURS
from WorkingShift, DutyRoster
WHERE DutyRoster, WorkingShiftID = WorkingShift, WorkingShiftID
AND EmployeeID = e;
IF TOTAL, WORKING HOURS > 35 THEN
SIGNAL SQLSTATE '45001' SET MESSAGE_TEXT = 'Employee is working over 35 hours....';
END IF;
END IF;
END
DELIMITER ;
DELIMITER //