On 06-Jul-01 Artem Koutchine wrote:
> Hi!
> There are two tables:

<random snipage>

> TASK:
> select all ids for names which are unique among both tables:
<snip>

> RETURNS: 3,4,5,6
> 
> The trick is to do it in ONE SQL statement.
> 

Why one ? is this a test ?

mysql> create table t (id int not null, name char(10), key(id)) 
     > TYPE=MERGE UNION=(a,b);
Query OK, 0 rows affected (0.00 sec)

mysql> select id, count(*) as cnt from t group by id having cnt=1;
+----+-----+
| id | cnt |
+----+-----+
|  3 |   1 |
|  4 |   1 |
|  5 |   1 |
|  6 |   1 |
+----+-----+
4 rows in set (0.00 sec)


Regards,
-- 
Don Read                                       [EMAIL PROTECTED]
-- It's always darkest before the dawn. So if you are going to 
   steal the neighbor's newspaper, that's the time to do it.

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