thank you Carlosdl, thank you all, its working now perfectly …

the thing is i just made the Group By according to the (auction_items.auction_item_nr) only … as below:

SELECT customers.first_name, customers.last_name, customers.email, customers.cellPhone, customers.phone,
items.title, items.price, auction_items.auction_item_nr, auction_items.reserv_price, MAX (biddings.price)
FROM customers, biddings, auction_items, items, auctions
WHERE customers.customer_nr = biddings.customer_nr
AND auction_items.auction_item_nr = biddings.auction_item_nr
AND items.item_nr = auction_items.item_nr
AND auction_items.auction_nr = auctions.auction_nr
AND auctions.auction_nr =7
GROUP BY auction_items.auction_item_nr
ORDER BY auction_items.item_nr

result is:
auction_items.auction_item_nr, auction_items.reserv_price, MAX (biddings.price)

50 450 400
50 450 300
51 300 300
52 8000 299
52 8000 199
48 1300 500
48 1300 400
49 800 500

as you can notice that the (auction_items.auction_item_nr) been duplicated two times for (50, 52, also 48), i don’t know what is the problem but it must gets like below …

auction_items.auction_item_nr, auction_items.reserv_price, MAX (biddings.price)

50 450 400
51 300 300
52 8000 299
48 1300 500
49 800 500

so any suggestion !!!

thank you for advance …