in oracle it does:
SQL> insert into x values ('1',null,'3');
insert into x values ('1',null,'3')
*
ERROR at line 1:
ORA-00001: unique constraint (DBA_USER.XIDX) violated
At 11:25 AM 7/20/00 -0400, Tom Lane wrote:
>mikeo <mikeo@spectrumtelecorp.com> writes:
>> insert into x values ('1','','3');
>
>> insert into x values ('1','','3')
>> *
>> ERROR at line 1:
>> ORA-00001: unique constraint (DBA_USER.XIDX) violated
>
>> i'd say that it finds 1,null,3 equal the 2nd time around...
>
>Surely '' does not mean NULL, especially not in a CHAR() column.
>
> regards, tom lane
>