Getting the "latest" related record from a SQL DB

[Gareth Harper]

In general I guess it's cleaner to do:

SELECT * FROM artist WHERE id = ?
SELECT * FROM album WHERE artist_id = ? ORDER BY release_date DESC LIMIT 1

OR

SELECT * from artist INNER JOIN album ON (artist.id = album.artist_id)
ORDER BY album.release_date DESC LIMIT 1

-

Gareth

On 9 October 2014 13:28, Andrew Beverley <andy at andybev.com> wrote:

> Hi guys,
>
> I'm after some best-practice advice regarding SQL database design.
>
> I have a table (say "artist", couldn't resist...) that has a one-to-many
> relationship to another table (say "album"). The album table has a field
> which references the artist table's ID. So one artist can have many
> albums.
>
> So, if I want to know all of an artist's albums, that's easy.
>
> But what if I want to fetch an artist's details and his latest album? I
> can select the artist from the artists table and then join the albums
> table. But to get the latest album I'd have to use a max function (say
> on the album's date), with which it isn't possible to get the related
> fields in the same row.
>
> I see 2 ways of solving this:
>
> - Run multiple queries to get the relevant album's ID (if even possible)
> and then retrieve its row in entirety.
>
> - Have a reference from the artist table back to the album table,
> specifying which is the latest album, which I update each time the
> albums table is updated.
>
> Neither seem particularly tidy to me, so am I missing something
> completely obvious?
>
> Thanks,
>
> Andy
>
>
>