如何破解While循环-出现错误：语法错误：缺少“冒号”

Question

我想中断SQL存储过程中的while循环，但出现错误“语法错误：缺少'冒号'”。

！[错误消息]：https://imgur.com/4tNVO9i

CREATE PROCEDURE `new_procedure` ()
BEGIN

    DECLARE COUNTER INT;
    DECLARE myvar INT;
    SET COUNTER = 0;
    SET myvar = 0;

    WHILE COUNTER < 5 DO

        IF myvar > 1 THEN
            INSERT INTO test (val) VALUES (1);
        ELSE
            BREAK; /* Here I get Syntax error: missing 'colon' */
        END IF;

        SET COUNTER = COUNTER + 1;

    END WHILE;

END