I am doing an election system, I am doing a graphic with ChartJS, so I need to COUNT votes GROUP BY date, then sum it with previous day

|voters_id|     created_at       |

6         20/07/2022
7         21/07/2022
9         21/07/2022
14        22/07/2022
21        22/07/2022

The output that I want is:

----------------------------------------- > (old + today) 
on date 20/07 i must have votation count= (0 +1) = 1 
on date 21/07 i must have votation count= (1 +2) = 3 
on date 22/07 i must have votation count= (3 +2) = 5 

How should I write this query?

>Solution :

You can use count() with windowing function. ie:

select distinct created_at, count(*) over (order by created_at) as votes
from mytable;

DBFiddle demo