MySQL循环遍历列中的每个值

DELIMITER //

CREATE PROCEDURE iterate_column_values()
BEGIN
    DECLARE done INT DEFAULT FALSE;
    DECLARE column_value VARCHAR(255);
    DECLARE cur CURSOR FOR SELECT column_name FROM table_name;
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

    OPEN cur;

    read_loop: LOOP
        FETCH cur INTO column_value;
        IF done THEN
            LEAVE read_loop;
        END IF;

        -- 在这里执行对每个值的操作
        -- 例如，可以将每个值打印出来
        SELECT column_value;

    END LOOP;

    CLOSE cur;
END //

DELIMITER ;