How to add values in sql? - postgresql

Question

I want to add the val_col based header_id and bill_name

Input:
bill_name header_id  va_col  id
23823     62259      40      7
23823     62259      7       8
23824     62254      20      7
23824     62254      40      9
23825     62257      10      7

Output:
bill_name header_id  total  
23823     62259      47
23824     62254      60           
23825     62257      10           

Answer 1

Seems like a very basic aggregation query:

select bill_name, 
       header_id, 
       sum(va_col) as total
from the_table
group by bill_name, header_id;