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CREATE TABLE table_name (datestamp) AS
SELECT '01/01/2022 01:23:45' FROM DUAL UNION ALL
SELECT '01/04/2022 01:23:45' FROM DUAL UNION ALL
SELECT '02/01/2022 01:23:45' FROM DUAL;
3 rows affected
SELECT to_char(to_date(Datestamp, 'MM/DD/YYYY HH24:MI:SS'), 'IW') AS iso_week
FROM table_name;
| ISO_WEEK |
|---|
| 52 |
| 01 |
| 05 |