Re: NULLs

I was too fast to press the Post button. A unique constraint on multiple columns behaves differently. It doesn't matter if I use NULL or a null string in this case:
create table test (a varchar2(1), b varchar2(1)); create unique index unq_test on test (a, b); insert into test values ('A', null);
insert into test values ('A', null);

I get unique constraint violated error. Sorry about the previous posting.

Yong Huang Received on Wed Dec 21 2005 - 16:50:46 CST