DECLARE @Table_Name VARCHAR(20) = 'table 1', @Update_Column VARCHAR(20) = 'Val4', @SQL NVARCHAR(MAX);

SELECT @SQL = 'UPDATE '+QUOTENAME(@Table_Name)+CHAR(13)+CHAR(10)+'SET '+QUOTENAME(@Update_Column)+' = CASE WHEN ' +
STUFF((SELECT ' OR ' +val
       FROM (SELECT name+'='+CHAR(39)+'.'+CHAR(39)
             FROM sys.columns
             WHERE object_id = OBJECT_ID(@Table_Name)
             AND name <> @Update_Column
             )a(val)
       FOR XML PATH(''), TYPE
       ).value('.','NVARCHAR(MAX)'),1,4,'')+' THEN '+CHAR(39)+'U'+CHAR(39)+' ELSE '+CHAR(39)+'u'+CHAR(39)+' END';

EXECUTE sp_executesql @SQL;

;with cte (val1, val2, val3)
as
(
	select 'asdf', 'qwer', 'rtyu' union all
	select 'as.df', 'yt', 'hhg' union all
	select 'weret', '99t4.rtkg9', ''
)

select case when CHARINDEX('.', val1 + val2 + val3) > 0 then 'U' else 'u' end
from cte