DECLARE @MyTable AS TABLE
(
Column1 INT,
Column2 INT, 
Column3 INT,
column4 INT
);

INSERT @MyTable VALUES (0,6,0,0);
INSERT @MyTable VALUES (0,0,30,0);
INSERT @MyTable VALUES (4,0,0,0);
INSERT @MyTable VALUES (1,2,3,18);

SELECT Col1 = MAX(Column1), Col2 = MAX(Column2), Col3 = MAX(Column3), Col4 = MAX(Column4) 
FROM @MyTable

SELECT Col1 = SUM(Column1), Col2 = SUM(Column2), Col3 = SUM(Column3), Col4 = SUM(Column4) 
FROM @MyTable


output from first statement:

       Col1        Col2        Col3        Col4
----------- ----------- ----------- -----------
          4           6          30          18


output from second statement:

       Col1        Col2        Col3        Col4
----------- ----------- ----------- -----------
          5           8          33          18