Question

Say I have two tables I want to join. Categories:

id   name ---------- 1    Cars 2    Games 3    Pencils 

And items:

id   categoryid   itemname --------------------------- 1    1            Ford 2    1            BMW 3    1            VW 4    2            Tetris 5    2            Pong 6    3            Foobar Pencil Factory 

I want a query that returns the category and the first (and only the first) itemname:

category.id category.name item.id item.itemname ------------------------------------------------- 1           Cars          1       Ford 2           Games         4       Tetris 3           Pencils       6       Foobar Pencil Factory 

And is there a way I could get random results like:

category.id category.name item.id item.itemname ------------------------------------------------- 1           Cars          3       VW 2           Games         5       Pong 3           Pencils       6       Foobar Pencil Factory 

Thanks!

Answer 1

Just done a quick test. This seems to work:

mysql> select * from categories c, items i     -> where i.categoryid = c.id     -> group by c.id; +------+---------+------+------------+----------------+ | id   | name    | id   | categoryid | name           | +------+---------+------+------------+----------------+ |    1 | Cars    |    1 |          1 | Ford           | |    2 | Games   |    4 |          2 | Tetris         | |    3 | Pencils |    6 |          3 | Pencil Factory | +------+---------+------+------------+----------------+ 3 rows in set (0.00 sec) 

I think this would fulfil your first question. Not sure about the second one – I think that needs an inner query with order by random() or something like that!