How to iterate this SQL query to go through specific date range?

Question

I am needing to extract three months at a time of one year for years 2016-2020. For example I need Jan-March in one file, Apr-Jun in another, etc. for each year.

The beginning of my SQL looks like so but I need it to go through years 2016-2020, extracting data three months at time.

    DECLARE @StartDateKey int = 20160101,
                @EndDateKey int = 20160331;

Answer 1

You code looks like SQL Server. You can use a recursive CTE:

with dates as (
      select convert(date, '20160101') as dte
      union all
      select dateadd(month, 3, dte)
      from dates
      where dte < '20201001'
     )
select *
from dates;

Here is a db<>fiddle.