Hive: Sum over a specified group (HiveQL)

Question

I have a table:

key    product_code    cost
1      UK              20
1      US              10
1      EU              5
2      UK              3
2      EU               


        

Answer 1

You could use BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW to achieve that without a self join.

Code as below:

SELECT a, SUM(b) OVER (PARTITION BY c ORDER BY d ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)
FROM T;