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From Ravinder Reddy <pand...@students.iiit.ac.in>
Subject regarding unique keys in derby..
Date Wed, 18 Jul 2007 19:02:14 GMT

 	hi all,
 		w.r.t DERBY-2945(convert lang/primarykey.sql to junit)
I have a small doubt.

There is a test for verifying a unique key can not contain nulls.

1)-- verify that a unique key can not contain nulls
   create table pos1 (c1 int not null unique, c2 int);
   insert into pos1 (c1) values(null);
   insert into pos1 (c1) values(null);
   select * from pos1;
   drop table pos1;
 	And It tests that null values are not allowed in c1.
 	Irrespective of uniqueness , c1 can't contain null values as it is 
defined as not null.It seems that the test is wrong.

2) I am shocked to know that Derby doesn't allow a unique key column to 
contain NULL values.can some somebody justify it.?

Thank You.


    Every problem that has been solved can be solved again in a better way

                                                   - Ravinder Reddy


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