create extension generate_date_series;
SET datestyle TO iso;
SELECT d.date_val FROM generate_date_series('1991-09-24'::date,'1991-10-01'::date) as d(date_val);
  date_val  
------------
 1991-09-24
 1991-09-25
 1991-09-26
 1991-09-27
 1991-09-28
 1991-09-29
 1991-09-30
 1991-10-01
(8 rows)

SELECT d.date_val FROM generate_date_series('1991-09-24'::date,'1991-10-02'::date,7) as d(date_val);
  date_val  
------------
 1991-09-24
 1991-10-01
(2 rows)

SELECT d.date_val FROM generate_date_series('1999-12-31'::date,'1999-12-29'::date,-1) as d(date_val);
  date_val  
------------
 1999-12-31
 1999-12-30
 1999-12-29
(3 rows)