Re: NOT IN queries

Nic Ferrier <nferrier(at)tapsellferrier(dot)co(dot)uk> writes:

> create table t1 (id integer, name varchar(20), t2_id integer);
> insert into t1 (id, name, t2_id) values (1, 'nic', 2);
> insert into t1 (id, name, t2_id) values (2, 'jim', NULL);
>
> create table t2 (id integer, name varchar(20));
> insert into t1 (id, name, t2_id) values (1, 'ferrier');
> insert into t1 (id, name, t2_id) values (2, 'broadbent');
>
> And now do this query:
>
> select * from t2 where id not in (select t2_id from t1);
>
> then I get a NULL response (ie: no rows returned).

Well, you never inserted any rows into t2, so that makes sense.

-Doug
--
Doug McNaught Wireboard Industries http://www.wireboard.com/

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