mysql if语句输出

IF condition THEN
    -- 当条件为真时执行的SQL语句
ELSE
    -- 当条件为假时执行的SQL语句
END IF;

DELIMITER //

CREATE PROCEDURE UpdatePosition()
BEGIN
    DECLARE emp_id INT;
    DECLARE emp_salary DECIMAL(10, 2);
    DECLARE emp_position VARCHAR(50);

    DECLARE cur CURSOR FOR SELECT id, salary FROM employees;
    OPEN cur;

    read_loop: LOOP
        FETCH cur INTO emp_id, emp_salary;
        IF emp_salary > 5000 THEN
            SET emp_position = '高级员工';
        ELSEIF emp_salary > 3000 THEN
            SET emp_position = '中级员工';
        ELSE
            SET emp_position = '初级员工';
        END IF;

        UPDATE employees SET position = emp_position WHERE id = emp_id;
    END LOOP;

    CLOSE cur;
END //

DELIMITER ;

DELIMITER //

CREATE PROCEDURE UpdatePosition()
BEGIN
    IF salary > 5000 THEN
        UPDATE employees SET position = '高级员工' WHERE id = 1;
    ELSE
        UPDATE employees SET position = '初级员工' WHERE id = 1;
    END IF;
END //

DELIMITER ;

DELIMITER //

CREATE PROCEDURE UpdatePosition()
BEGIN
    DECLARE emp_id INT;
    DECLARE emp_salary DECIMAL(10, 2);

    SET emp_id = 1;
    SELECT salary INTO emp_salary FROM employees WHERE id = emp_id;

    IF emp_salary > 5000 THEN
        UPDATE employees SET position = '高级员工' WHERE id = emp_id;
    ELSE
        UPDATE employees SET position = '初级员工' WHERE id = emp_id;
    END IF;
END //

DELIMITER ;