composite Unique constraint and null 2005-10-18 - By Mercadante, Thomas F (LABOR)
Sandeep,
It seems like your uniqueness rule backwards.
What you really want is uniqueness on the second column only. The id
column just doesn't matter (at least given the example you gave us
below), right?
Tom
-- --Original Message-- --
From: oracle-l-bounce@(protected)
[mailto:oracle-l-bounce@(protected)] On Behalf Of Sandeep Dubey
Sent: Tuesday, October 18, 2005 1:06 PM
To: oracle-l@(protected)
Subject: composite Unique constraint and null
Hi,
I want to enforce a business rule on two columns such that col1, col2
should be unique. However for a given value of col1 nulls should be
allowed in col2. I can not implement that using a simple composite
unique constraint.
Eg.
create table foo(id number, name varchar2(10));
insert into foo values(1,1);
insert into foo values(1,1); -- should not be allowed
But following should be allowed
insert into foo values(1,null);
insert into foo values(1,null); -- should be allowed
Any ideas!!
Thanks
Sandeep
Sandeep
--
http://www.freelists.org/webpage/oracle-l
--
http://www.freelists.org/webpage/oracle-l
|
|
