如何从IBM DB2中的当前日期开始获取过去4年中每个月的第一天和最后一天？

WITH date_range AS (
  SELECT CURRENT_DATE - (4 * 365) AS start_date, CURRENT_DATE AS end_date
  FROM SYSIBM.SYSDUMMY1
)
SELECT 
  DATE(DATE_RANGE.start_date + (ROW_NUMBER() OVER() - 1) MONTH) AS first_day,
  LAST_DAY(DATE(DATE_RANGE.start_date + (ROW_NUMBER() OVER() - 1) MONTH)) AS last_day
FROM date_range
CROSS JOIN TABLE (VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12)) AS months(month)
WHERE DATE(DATE_RANGE.start_date + (ROW_NUMBER() OVER() - 1) MONTH) <= DATE_RANGE.end_date
ORDER BY first_day