Re: One to many query question

Dave Dribin wrote:

>Hi, I'm having trouble with what I think should be an easy query. For
>simplicity, I will use a CD database as an example. Each CD may have
>multiple genres. Here's some sample data:
>
>Artist Title Genres
>---------------------- ------------------------------ ----------------
>Miles Davis Some Kind of Blue Jazz
>Metallica Ride the Lightning Rock
>Chemical Brothers Surrender Electronic
>Radiohead OK Computer Rock, Electronic
>
>For simplicities sake, let's ignore normalization on artist and genre,
>and say the tables look like:
>
>CREATE TABLE cd (
> id integer unique,
> artist varchar(25),
> title varchar(25)
>);
>
>CREATE TABLE cd_genres (
> cd_id integer,
> genre varchar(25)
>);
>
>How do I write a query to find all CDs that are NOT Rock?
>
What about
select * from cd where not exists (select 1 from cd_genres where cd_id
= cd.id and genre='Rock')?

Dima