Postgres 15

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CREATE TABLe transactions (transaction_time date,transaction_amount decimal(10,2))

CREATE TABLE


select 
    Sum_pDay.day
    , Sum_pDay.Month
    , Sum_pDay.Year
     ,  avg (SUM(Sum_pDay.SumAmount)) over (order by Sum_pDay.day rows between 2 preceding and current row) as Avg
from (
  select 
    extract (year from transaction_time) as Year
      , extract (month from transaction_time) as Month
      , extract (day from transaction_time) as day
      , sum (transaction_amount) as SumAmount
     from
        transactions
     group by Year, Month, day
     order by 3) as Sum_pDay
group by 1,2,3


day
month
year
avg



SELECT 0


select 
    Sum_pDay.day
    , Sum_pDay.Month
    , Sum_pDay.Year
     ,  avg (Sum_pDay.SumAmount) over (order by Sum_pDay.day rows between 2 preceding and current row) as Avg
from (
  select 
    extract (year from transaction_time) as Year
      , extract (month from transaction_time) as Month
      , extract (day from transaction_time) as day
      , sum (transaction_amount) as SumAmount
     from
        transactions
     group by Year, Month, day
     order by 3) as Sum_pDay


day
month
year
avg



SELECT 0