By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.
select *
into parent
from (values (1, 2016, 2020, 2.0),
(2, 2018, 2021, 3.5)
) v(ID, StartYear, EndYear, Capacity)
2 rows affected
with cte as ( -- may require "recursive" keyword
select id, startyear as year, capacity, endyear
from parent
union all
select id, year + 1, capacity, endyear
from cte
where year < endyear
)
select id, year, capacity
from cte
order by id, year;
| id | year | capacity |
|---|---|---|
| 1 | 2016 | 2.0 |
| 1 | 2017 | 2.0 |
| 1 | 2018 | 2.0 |
| 1 | 2019 | 2.0 |
| 1 | 2020 | 2.0 |
| 2 | 2018 | 3.5 |
| 2 | 2019 | 3.5 |
| 2 | 2020 | 3.5 |
| 2 | 2021 | 3.5 |