mysql中如何写循环

WITH RECURSIVE employee_hierarchy AS (
    -- Anchor member: select the initial employee
    SELECT id
    FROM employees
    WHERE id = ? -- Replace ? with the starting employee ID

    UNION ALL

    -- Recursive member: select all subordinates of the current set
    SELECT e.id
    FROM employees e
    INNER JOIN employee_hierarchy eh ON e.manager_id = eh.id
)
SELECT id FROM employee_hierarchy;

DELIMITER //

CREATE PROCEDURE InsertNumbers(IN start INT, IN end INT)
BEGIN
    DECLARE i INT DEFAULT start;

    WHILE i <= end DO
        INSERT INTO numbers (value) VALUES (i);
        SET i = i + 1;
    END WHILE;
END //

DELIMITER ;

-- 调用存储过程
CALL InsertNumbers(1, 10);

CREATE TEMPORARY TABLE temp_sales AS
SELECT product_id, SUM(amount) as total_sales
FROM orders
GROUP BY product_id;

SELECT p.name, t.total_sales
FROM products p
JOIN temp_sales t ON p.id = t.product_id;