NVL VS CASE

Here a quick example of how NVL and CASE can be switched to improve performance and readability.


--  CASE VERSION with X097_TEMP_EDIT_TO_DNI_TRANSACT
SELECT
( CASE    WHEN  x097.c097_edit_name  IS NULL THEN  t097.c097_edit_name  ELSE  x097.equip_stn_no END
   ) as c097_edit_name,
  t097.c097_edit_name as tempHistoric,  x097.equip_stn_no
 FROM t097_temp_edit_his  t097,  X097_TEMP_EDIT_TO_DNI_TRANSACT x097, CIRCUIT
 where t097.c097_edit_name =x097.c097_edit_name (+)
 AND    6100006 = circuit.circt_id (+)
and rownum < 10;



--  NVL VERSION with X097_TEMP_EDIT_TO_DNI_TRANSACT

SELECT   NVL(x097.equip_stn_no , t097.c097_edit_name ) as c097_edit_name,
x097.equip_stn_no END    ) as c097_edit_name,
  t097.c097_edit_name as tempHistoric,  x097.equip_stn_no
 FROM t097_temp_edit_his  t097,  X097_TEMP_EDIT_TO_DNI_TRANSACT x097, CIRCUIT
 where t097.c097_edit_name =x097.c097_edit_name (+)
 AND    6100006 = circuit.circt_id (+)
and rownum < 10;