sqlʹÓÃcast½øÐÐÊý¾ÝÀàÐÍת»»

@num=1;

°ÑnumÀàÐÍת³ÉnvarcharÀàÐÍ

cast£¨@num as nvarchar(10)£©

@str='123';

°Ñstrת»»³Éint ÀàÐÍ

cast£¨@str as int£©