SQL Query to Find Latest Activity Date for Employees by Department

SELECT t.departmentid, t.id, t.lastname, t.jobtitle, f.actime FROM hrmresource t LEFT JOIN (SELECT * FROM (SELECT b.*, ROW_NUMBER() OVER (PARTITION BY person ORDER BY actime DESC) AS rn FROM (SELECT * FROM (SELECT changedate as actime, resourceid as person FROM hrmstatushistory WHERE resourceid IN (2182, 4122, 224, 2564, 2169, 799, 782, 795, 792) UNION ALL SELECT adjust_date as actime, adjust_person as person FROM uf_adjust_history WHERE adjust_person IN (2182, 4122, 224, 2564, 2169, 799, 782, 795, 792)) ORDER BY actime desc) b) subquery WHERE rn = 1) f ON t.id = f.person WHERE t.id IN (2182, 4122, 224, 2564, 2169, 799, 782, 795, 792) GROUP BY t.departmentid ORDER BY f.actime