Switch case (UPDATE)

UPDATE m_lmr_period
SET lmr_status = CASE
   WHEN lmr_status IN ('P') THEN 'O'
   WHEN lmr_status IN ('C') THEN 'P'
   ELSE 'O'
END

UPDATE m_lmr_period

SET lmr_status = CASE

WHEN lmr_status IN ('P') THEN 'O'

WHEN lmr_status IN ('C') THEN 'P'

ELSE 'O'

END