INSERT 
INTO DEPARTMENT( 
   DEPT_CODE
   , START_DATE
   , END_DATE
   , DEPT_NAME
   , LAYER
   , UP_DEPT_CODE
   , VALID_FLG
   , UPDATE_USER_NAME
) 
SELECT
     'B300'
   , '2023-04-01'
   , NULL
   , '新設部門'
   , LAYER
   , UP_DEPT_CODE
   , '1'
   , UPDATE_USER_NAME 
FROM
   DEPARTMENT 
WHERE
   DEPT_CODE = 'A100'
; 

UPDATE DEPARTMENT 
SET
   END_DATE = '2023-03-31'
   , VALID_FLG = '0'
   , UPDATE_USER_NAME = 'ORG_CHG'
   , USER_UPDATE_DATETIME = '2023-03-31 23:59:59' 
WHERE
   DEPT_CODE IN ('A100', 'A200')
; 

UPDATE EMP 
SET
   DEPT_CODE = 'B300'
   , START_DATE = '2023-04-01'
   , UPDATE_USER_NAME = 'ORG_CHG'
   , USER_UPDATE_DATETIME = '2023-04-01 00:00:00' 
WHERE
   DEPT_CODE IN ('A100', 'A200') 
   AND VALID_FLG = '1'
; 

-- SELECT
--      * 
-- FROM
--   DEPARTMENT
-- ; 

-- SELECT
--      * 
-- FROM
--   EMP
-- ;