Hive - sql max number with multiple rows - hive

Question

For the raw data below, how do I get max number per customer_id for the entire row and null for rest of the row? I can get the max for the data but not able to get in the form #Results
#Raw data
customer_id name location itemno_1 itemno_2 itemno_3 itemno_4 itemno_5
123 Ashley M CA 10 null 10 null null
123 Ashley M CA null 12 null 12 null
143 Donald P FL 15 15 0 1 10
187 Alicia P GA 15 9 null null null
1736 Mike H CT null 8 8 9 null
1736 Mike H CT null null null null null
1876 David M CA null null null null null
532 Matthew T CA null 9 10 10 null
Results
customer_id name location itemno_1 itemno_2 itemno_3 itemno_4 itemno_5
123 Ashley M CA null 12 null null null
143 Donald P FL 15 null null null null
187 Alicia P GA 15 null null null null
1736 Mike H CT null null null null null
1876 David M CA null null null null null
532 Matthew T CA null null null 10 null

Answer 1

Below is the query which produces your expected result.(I have tested it works) I have assumed if 2 item_nos have same max value we will keep value in lowest item_no. For example for customer_id = 123 itemno_2 and itemno_4 has value 12 but kept itemno_2 as 12 and made itemno_4 as null.
select customer_id, name, location1
,CASE WHEN (i1 >= i2 or i2 is null)
AND (i1 >= i3 or i3 is null)
AND (i1 >= i4 or i4 is null)
AND (i1 >= i5 or i5 is null)
THEN i1
ELSE null
END as itemno_1
,CASE WHEN (i2 >= i1 or i1 is null)
AND (i2 >= i3 or i3 is null)
AND (i2 >= i4 or i4 is null)
AND (i2 >= i5 or i5 is null)
AND (i1 <> i2 or i1 is null)
THEN i2
ELSE null
END as itemno_2
,CASE WHEN (i3 >= i1 or i1 is null)
AND (i3 >= i2 or i2 is null)
AND (i3 >= i4 or i4 is null)
AND (i3 >= i5 or i5 is null)
AND (i1 <> i3 or i1 is null)
AND (i2 <> i3 or i2 is null)
THEN i3
ELSE null
END as itemno_3
,CASE WHEN (i4 >= i1 or i1 is null)
AND (i4 >= i2 or i2 is null)
AND (i4 >= i3 or i3 is null)
AND (i4 >= i5 or i5 is null)
AND (i1 <> i4 or i1 is null)
AND (i2 <> i4 or i2 is null)
and (i3 <> i4 or i3 is null)
THEN i4
ELSE null
END as itemno_4
,CASE WHEN (i5 >= i1 or i1 is null)
AND (i5 >= i2 or i2 is null)
AND (i5 >= i3 or i3 is null)
AND (i5 >= i4 or i4 is null)
AND (i1 is null or i1 <> i5)
AND (i2 is null or i2 <> i5)
AND (i3 is null or i3 <> i5)
AND (i4 is null or i4 <> i5)
THEN i5
ELSE null
END as itemno_5
from (
select customer_id, name, location1
,max(itemno_1) as i1
,max(itemno_2) as i2
,max(itemno_3) as i3
,max(itemno_4) as i4
,max(itemno_5) as i5
from default.stack2
group by customer_id, name, location1) a
order by customer_id;
Same thing can also be achieved by writing UDF instead of case statements to find maximum of 5 columns and return as expected.