JOIN problem

[eluser]danmontgomery[/eluser]
There isn't a way to do what you're describing, since that would require a result set with two identically named columns. What you probably want is GROUP_CONCAT, which will return all of the product_id's as a string in one field, you can specify a separator and explode them out that way. You'll also need to GROUP the results to get what you want.

SELECT `orders`.`id`, `orders`.`order_date`, `orders_items`.`order_id`, GROUP_CONCAT( DISTINCT `orders_items`.`product_id` SEPARATOR '|' ) AS product_ids
FROM (`orders`)
JOIN `orders_items` ON `orders_items`.`order_id` = `orders`.`id`
WHERE `orders`.`customer_id` = '19'
GROUP BY `orders`.`id`

Should work for you, returning the multiple product id's as the string "1|3". (The 'DISTINCT' is probably optional, it will only give you distinct values in the case that there are 2 records for an order with the same product id).