Can anyone explain the logic in this for me??

Now this is a bit puzzling...

  1* SELECT 'X' FROM DUAL WHERE '' = NULL SQL> / no rows selected

Elapsed: 00:00:00.00
SQL> SELECT 'X' FROM DUAL WHERE '' IS NULL   2 /

'
-
X

Now why is the empty string ( '' ) <> null but the same empty string IS NULL ?

JP Received on Fri Mar 01 2002 - 21:19:04 CET