MySQL 8.0

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create table purchases (accountid text, purchase_date date, productid text);
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-01', '534ad451f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-02', '534ad451f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-03', '534ad451f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-04', '534ad451f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-05', '0f9d321ad');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-06', '0f9d321ad');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-07', '534ad451f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-08', '4a5d93a1f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-09', '4a5d93a1f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-10', '4a5d93a1f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-10', '534ad451f');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-10', '0f9d321ad');
insert into purchases (accountid, purchase_date , productid) values ('a1', '2022-01-11', '9cd018fc0');
with byMinDate as (
    select *,
      row_number() over (partition by accountid, productid
          order by purchase_date) as rn
    from purchases
)
select
  accountid,
  purchase_date,
  sum(rn = 1) as new_distinct_rows,
  sum(sum(rn = 1)) over (partition by accountid order by purchase_date rows unbounded preceding) as running_distinc_count
from byMinDate
group by
  accountid,
  purchase_date;


accountid
purchase_date
new_distinct_rows
running_distinc_count


a1
2022-01-01
1
1

a1
2022-01-02
0
1

a1
2022-01-03
0
1

a1
2022-01-04
0
1

a1
2022-01-05
1
2

a1
2022-01-06
0
2

a1
2022-01-07
0
2

a1
2022-01-08
1
3

a1
2022-01-09
0
3

a1
2022-01-10
0
3

a1
2022-01-11
1
4


with byMinDate as (
    select *,
      row_number() over (partition by accountid, productid
          order by purchase_date) as rn
    from purchases
)
select
  accountid,
  purchase_date,
  count(*) as new_distinct_rows,
  sum(count(*)) over (partition by accountid order by purchase_date rows unbounded preceding) as running_distinc_count
from byMinDate
where rn = 1
group by
  accountid,
  purchase_date;


accountid
purchase_date
new_distinct_rows
running_distinc_count


a1
2022-01-01
1
1

a1
2022-01-05
1
2

a1
2022-01-08
1
3

a1
2022-01-11
1
4

accountid	purchase_date	new_distinct_rows	running_distinc_count
a1	2022-01-01	1	1
a1	2022-01-02	0	1
a1	2022-01-03	0	1
a1	2022-01-04	0	1
a1	2022-01-05	1	2
a1	2022-01-06	0	2
a1	2022-01-07	0	2
a1	2022-01-08	1	3
a1	2022-01-09	0	3
a1	2022-01-10	0	3
a1	2022-01-11	1	4