单个if中的多个或运算符

如何在单个if语句中使用多个或运算符?我试过这种方法,但有一个错误:

表达式或赋值中的数据类型不兼容。

我看过长度函数的文档,它是 LENGTH ( {string | raw-expression | blob-field } [ , type ] ) ?

代码如下:

DEFINE VARIABLE cMonth AS CHARACTER.
DEFINE VARIABLE cDay AS CHARACTER.
DEFINE VARIABLE cYear AS CHARACTER.

UPDATE cDateFromUser.

cDay = (SUBSTRING(cDateFromUser,1,2)).
cMonth = (SUBSTRING(cDateFromUser,3,2)).
cYear = (SUBSTRING(cDateFromUser,5,4)).

IF (LENGTH(cDay <> 2)) OR (LENGTH(cMonth <> 2)) OR (LENGTH(cYear <> 4)) THEN DO:
    /*Code*/
END.
ELSE DO:
    /*Code*/
END.