https://bbs.csdn.net/topics/390480323ISNUMERIC(size_long)=1(IIF( ISNUMERIC(size_long)=1 AND ISNUMERIC(size_wide)=1AND ISNUMERIC(size_high)=1 ,CONVERT(DECIMAL,size_high)+CONVERT(DECIMAL,size_long)+CONVERT(DECIMAL,size_wide),0)