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create table tablename(Account varchar(20), Date date, Value int);
insert into tablename(Account, Date, Value) values
('Account 1', '2019-01-01', 12),
('Account 1', '2019-01-03', 32),
('Account 1', '2019-01-12', 52),
('Account 2', '2018-04-01', 123),
('Account 2', '2018-04-22', 42),
('Account 3', '2019-02-01', 11),
('Account 3', '2018-07-01', 64),
('Account 3', '2018-08-12', 74);
select sum(t.value) totalvalue
from tablename t inner join (
select account, max(date) date
from tablename
group by account
) g on g.account = t.account and g.date = t.date
| totalvalue |
|---|
| 105 |
select sum(t.value) totalvalue
from tablename t
where not exists (
select 1 from tablename
where account = t.account and date > t.date
)
| totalvalue |
|---|
| 105 |