4.sql

with data as (
    select
    current_timestamp() as ts           
    ,'stage'            as context_type 
    ,1                  as user_id      
    ,100                as credit_value 
    , true              as is_gift
union all
    select
    timestamp_sub(current_timestamp(), interval 24 hour) as ts           
    ,'user'             as context_type 
    ,1                  as user_id      
    ,200                as credit_value 
    ,false              as is_gift
union all
    select
    timestamp_sub(current_timestamp(), interval 24*2 hour) as ts           
    ,'user'             as context_type 
    ,3                  as user_id      
    ,300                as credit_value 
    ,true               as is_gift

)
, results as (
select 
     date(ts) as date 
    ,context_type
    ,sum(credit_value)/100 as daily_credits_spend
from data    

group by rollup(1, context_type)
order by 1
)

select
  date
  ,if(context_type is null, 'total', context_type) as context_type
  ,daily_credits_spend
from results
order by date
;