mikeo <mikeo(at)spectrumtelecorp(dot)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