Oracle 21c

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ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
ALTER SESSION SET NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF';
WITH input (month) AS (
  SELECT DATE '2023-02-01' FROM DUAL
),
calendar (week_start) AS (
  SELECT TRUNC(TRUNC(month, 'MM'), 'IW') + 7 * (LEVEL - 1)
  FROM   input
  CONNECT BY TRUNC(TRUNC(month, 'MM'), 'IW') + 7 * (LEVEL - 1)
         < ADD_MONTHS(TRUNC(month, 'MM'), 1)
)
SELECT week_start,
       week_start + INTERVAL '6 23:59:59' DAY TO SECOND AS week_end
FROM   calendar


WEEK_START
WEEK_END


2023-01-30 00:00:00
2023-02-05 23:59:59

2023-02-06 00:00:00
2023-02-12 23:59:59

2023-02-13 00:00:00
2023-02-19 23:59:59

2023-02-20 00:00:00
2023-02-26 23:59:59

2023-02-27 00:00:00
2023-03-05 23:59:59

WEEK_START	WEEK_END
2023-01-30 00:00:00	2023-02-05 23:59:59
2023-02-06 00:00:00	2023-02-12 23:59:59
2023-02-13 00:00:00	2023-02-19 23:59:59
2023-02-20 00:00:00	2023-02-26 23:59:59
2023-02-27 00:00:00	2023-03-05 23:59:59