Пример функции MySQL

function.sql

create
    definer = root@`::1` function updatePublicWorksDate(serviceLogId int, date date, dateId varchar(255)) returns date
BEGIN

  IF (dateId = 'REFERRAL_DATE') THEN
    UPDATE m_service_public_works mspw
    SET mspw.REFERRAL_DATE = date
    WHERE mspw.SERVICE_LOG_ID = serviceLogId;
  END IF;

  IF (dateId = 'PW_SENT_DATE') THEN
    UPDATE m_service_public_works mspw
    SET mspw.PW_SENT_DATE = date
    WHERE mspw.SERVICE_LOG_ID = serviceLogId;
  END IF;

  IF (dateId = 'PW_DENY_DATE') THEN
    UPDATE m_service_public_works mspw
    SET mspw.PW_DENY_DATE = date
    WHERE mspw.SERVICE_LOG_ID = serviceLogId;
  END IF;

  IF (dateId = 'PW_STOP_DATE') THEN
    UPDATE m_service_public_works mspw
    SET mspw.PW_STOP_DATE = date
    WHERE mspw.SERVICE_LOG_ID = serviceLogId;
  END IF;

  IF (dateId = 'PW_USE_DATE') THEN
    UPDATE m_service_public_works mspw
    SET mspw.PW_USE_DATE = date
    WHERE mspw.SERVICE_LOG_ID = serviceLogId;
  END IF;

  RETURN date;
END;