Joining multiple (normalized) tables

[liljeboy]

Hi all, I'm a n00b here and I'm loving it!
This is my first post so I appologize for any and all errors I make.

I'd like to ask a question about a sql query,
I have no idea how to join tables, so a little
help would come very handy!

Here are three queries that will get me what I need,
but I want to turn them into only one query if possible.

I start out by knowing the trade_id, which is '1':

SELECT seller_id FROM relations WHERE trade_id = '1';

--- result -------------------
seller_id: '2'

Then, I need to get the location_id from the sellers table using the seller_id:

SELECT location_id FROM sellers WHERE seller_id = '2';

--- result -------------------
location_id: '338'

And finally, I need to get the location title from locations table using the location_id:

SELECT location_title FROM locations WHERE location_id = '338'

--- result -------------------
location_title: Stockholm

I've read most any tutorial I can find on the subject
but I cant seem to understand what's going on in them..

I've tried this with no luck:

SELECT location_title
FROM locations
INNER JOIN relations ON trade_id = '1'
INNER JOIN sellers ON sellers.seller_id = relations.seller_id

Anyone have any suggestions or pointers?

Many thanks for reading!

• Andrew

[bpat1434]

Try this....

SELECT a.seller_id, b.location_id, c.location_title
FROM locations AS a
JOIN relations AS b ON a.seller_id=b.location_id
JOIN sellers ON b.location_id=c.location_id
WHERE trade_id='1'

~Brett

[liljeboy]

many thanks!!!!!!!!!!!!!!!!!!!!!!!!!!!!