mysql怎么循环语句

DELIMITER //

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

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

DELIMITER ;

CALL simple_while_loop();

DELIMITER //

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

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

DELIMITER ;

CALL simple_repeat_loop();

DELIMITER //

CREATE PROCEDURE simple_loop()
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 ;

CALL simple_loop();