mysql 循环语句写哪

DELIMITER //

CREATE PROCEDURE WhileLoopDemo()
BEGIN
    DECLARE counter INT DEFAULT 1;

    WHILE counter <= 5 DO
        SELECT counter;
        SET counter = counter + 1;
    END WHILE;
END //

DELIMITER ;

DELIMITER //

CREATE PROCEDURE RepeatLoopDemo()
BEGIN
    DECLARE counter INT DEFAULT 1;

    REPEAT
        SELECT counter;
        SET counter = counter + 1;
    UNTIL counter > 5 END REPEAT;
END //

DELIMITER ;

DELIMITER //

CREATE PROCEDURE LoopDemo()
BEGIN
    DECLARE counter INT DEFAULT 1;

    loop_label: LOOP
        SELECT counter;
        SET counter = counter + 1;

        IF counter > 5 THEN
            LEAVE loop_label;
        END IF;
    END LOOP;
END //

DELIMITER ;