I have 4 tables: bol, eci, ako, voordeel_boeken_online. Some of the tables has a price for the book with isbn 9780002261357. I checked it with the following query:
SELECT bol.price as bol_price
, eci.price as eci_price
, ako.price as ako_price
, voordeel_boeken_online.price AS voordeel_boeken_online_price
FROM books
LEFT
JOIN bol
ON bol.product_id = bol_id
LEFT
JOIN eci
ON eci.product_id = eci_id
LEFT
JOIN voordeel_boeken_online
ON voordeel_boeken_online.product_id = voordeel_boeken_id
LEFT
JOIN ako
ON ako.product_id = ako_id
WHERE isbn = '9780002261357'
ORDER
BY bol.price
, eci.price
, ako.price
, voordeel_boeken_online.price
But it gives me this output:
I want the lowest price first, but it doesn't do that. What am I doing wrong?