ALTER TABLE DAYSUM
  MODIFY V_TOT_REVN NUMBER GENERATED ALWAYS AS (ROUND(NVL("RM_REVN",0)+NVL("FB_REVN",0)+NVL("RM_UPGRADES",0)+NVL("OTHER_REVN",0)+NVL("DIVE_SERV",0)+NVL("DIVE_EQUIP",0),2)) VIRTUAL