Question

I’m trying to do a homework problem that requires.

--5. CALCULATE THE TOTAL QUANTITY ON HAND FOR EACH INVENTORY IT IN THE INVENTORY
--TABLE-IGNORE THIER DIFFERNT SIZES AND COLORS

This is the query I’ve come with. I looks right except for the qoh value

SELECT DISTINCT(item.item_id),item.item_desc,
(SELECT SUM(inv_qoh) FROM INVENTORY WHERE i.item_id = item.item_id)
FROM ITEM item INNER JOIN INVENTORY i ON i.item_id = item.item_id;

Each rows returns 3143 instead of the value for that specific item_id.

     5 Children's Beachcomber Sandals                                                         3143 
     7 Girl's Soccer Tee                                                                      3143 
     4 Women's Fleece Pullover                                                                3143 
     6 Boy's Surf Shorts                                                                      3143 
     1 Men's Expedition Parka                                                                 3143 
     3 Women's Hiking Shorts                                                                  3143 
     2 3-Season Tent                                                                          3143 

Answer 1

It seems like you want to use something like this. It applies the sum() aggregate and a GROUP BY to the remaining two fields in your SELECT list:

SELECT item.item_id, 
    item.item_desc,
    SUM(i.inv_qoh) TotalInventory
FROM ITEM item 
INNER JOIN INVENTORY i 
    ON item.item_id = i.item_id
GROUP BY item.item_id, item.item_desc;