Akumulasi ( Rolling Sum ) SQL

Contoh :

Date                    Sales           Running Total Of Sales
10/1/2015             5                           5
10/2/2015             3                           8
10/3/2015             7                         15
10/4/2015             8                         23
10/5/2015             2                         25
10/6/2015             3                         28
10/7/2015             6                         34

Cara 1.

select

a.date,

sum(b.sales) as cumulative_sales

from sales_table a

join sales_table b on a.date >= b.date

group by a.date

order by a.date;

Cara 2.

select

date,

sum(sales) over (order by date rows unbounded preceding) as cumulative_sales

from sales_table;



source:https://www.wagonhq.com/blog/running-totals-sql