Hi,
============================================================================
                        POSTGRESQL BUG REPORT TEMPLATE
============================================================================
Your name        : Jan Vitek
Your email address    : jvit8627@ss1000.ms.mff.cuni.cz
System Configuration
---------------------
  Architecture (example: Intel Pentium)      : AMD Pentium
  Operating System (example: Linux 2.0.26 ELF)     : Linux 2.2.10 ELF
  PostgreSQL version (example: PostgreSQL-6.5.3): PostgreSQL-6.5.3
  Compiler used (example:  gcc 2.8.0)        : gcc 2.7.2.3
Please enter a FULL description of your problem:
------------------------------------------------
Intersect operator doesn't work as it would under some circumstances,
which i describe below.
I have found this simplest example:
$ psql data <<EOF
create table num (n int4);
insert into num values (1);
insert into num values (null);
select * from num intersect select * from num;
select distinct * from num intersect select * from num;
drop table num;
EOF
create table num (n int4);
CREATE
insert into num values (1);
INSERT 448713 1
insert into num values (null);
INSERT 448714 1
select * from num intersect select * from num;
n
-
1
(2 rows)
select distinct * from num intersect select * from num;
n
-
1
(1 row)
drop table num;
DROP
$
I think that the result of the second select is wrong and should be the
same as the result of the first select. This behaviour happens only,
when there is a null in some field.
Jan Vitek <jvit8627@ss1000.ms.mff.cuni.cz>