mysql 删除游标

DELIMITER //

CREATE PROCEDURE process_data()
BEGIN
    DECLARE done INT DEFAULT FALSE;
    DECLARE v_id INT;
    DECLARE v_name VARCHAR(255);
    DECLARE cur CURSOR FOR SELECT id, name FROM your_table;
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

    OPEN cur;

    read_loop: LOOP
        FETCH cur INTO v_id, v_name;
        IF done THEN
            LEAVE read_loop;
        END IF;
        -- 在这里进行数据处理，如删除操作
        DELETE FROM your_table WHERE id = v_id;
    END LOOP;

    CLOSE cur;
END //

DELIMITER ;

DELIMITER //

CREATE PROCEDURE delete_data()
BEGIN
    DECLARE done INT DEFAULT FALSE;
    DECLARE v_id INT;
    DECLARE cur CURSOR FOR SELECT id FROM your_table WHERE some_condition = 'some_value';
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;

    OPEN cur;

    read_loop: LOOP
        FETCH cur INTO v_id;
        IF done THEN
            LEAVE read_loop;
        END IF;
        DELETE FROM your_table WHERE id = v_id;
    END LOOP;

    CLOSE cur;
END //

DELIMITER ;