
I have 2 table say c1,c2 (same attributes) and then I would like to 

CREATE VIEW c AS 
  SELECT * FROM c1 
  UNION  
  SELECT * FROM c2;

But the system not accept. (not implement)
Then I change to use 
CRATE TABLE c (<** attributes are same as c1,c2 **>)
CREATE RULE r1 AS ON SELECT to c 
  DO INSTEAD 
  SELECT * FROM c2 
  UNION 
  SELECT * FROM c1;

Tbe system accept this rule but when I process 'SELECT * FROM c1;', the
result is not sastified; only tuples on c2 are display.

Is there other way to get result like above. One I've thought in mind is:-
CREATE RULE r1 AS ON SELECT to c
  DO INSTEAD
  SELECT funct_UNION(c1,c2);
But I have no idea how to do kinds of the function that return set of
tuple

WChart.



Mon, 10 May 1999 15:51:16 +0700 (GMT)
Werachart  Jantarataeme <it072560@it.kmutt.ac.th>
How can I use UNION in VIEW/RULE? 