SQL query not working properly (not sure about it) - sql

Question

I have 2 tables: ORDER_INFO_TABLE and APPROVE_TABLE
The first one contains the information related to "orders".. DO NOTE that a single order may contain different "order lines" (thats why you'll see the order number repeated in the image below).Also, there exist a field called "PRICE" (this field is not SHOWN in my image) and CANCELLED (order line status)
The second table contains the information related to the "approvers" for the different order lines. Inside this table you will see a field called "APPROVERID", ITEMID (order line id) and "APPROVED" (order line status). The approvers must check if the price is okay or not. If the order line is okay, the approver will put a number 1 in the field "APPROVED". If the price is not correct, he will put a number 1 in the field CANCELLED in the other table.
Take a look at these images:
I have tried without success to obtain all the cancelled orders (an order is cancelled when all ITS order lines are cancelled) AND the approved order (an approved order may contain cancelled order lines) for an specific approver
I tried so many times, using count operator, left join but i am completely lost :(
A guy suggested me to use this query:
SELECT web_order_id
FROM ORDER_INFO_TABLE oif
INNER JOIN APPROVE_TABLE apt
ON (oif.item_id = apt.item_id)
GROUP BY web_order_id
HAVING SUM(cancelled) = COUNT(*);
The problem is that it is not woking properly (it shows this error message: operand data type is invalid for sum operator) AND using this query i will not be able to obtain the CANCELLED and APPROVED orders for a specific approver.
EDIT:
SELECT web_order_id
FROM ORDER_INFO_TABLE oif
INNER JOIN APPROVE_TABLE apt
ON (oif.item_id = apt.item_id **and apt.APPROVERID = 'RANDOM#MAILNATOR.COM'**)
GROUP BY web_order_id
HAVING SUM(cancelled) = COUNT(*);

Answer 1

Edited: If you just want to select order from specific approver then just use simple select with join:
SELECT oif.web_order_id, oif.item_id, apt.approverid,
oif.cancelled, apt.approved
FROM ORDER_INFO_TABLE oif
INNER JOIN APPROVE_TABLE apt
ON oif.item_id = apt.item_id
WHERE apt.approverid = 'RANDOM#MAILNATOR.COM'
ORDER BY oif.web_order_id, oif.item_id;
Seems that your cancelled column datatype is VARCHAR. You should convert it to number before using SUM function
SELECT oif.web_order_id
FROM ORDER_INFO_TABLE oif
INNER JOIN APPROVE_TABLE apt
ON oif.item_id = apt.item_id
GROUP BY oif.web_order_id
HAVING SUM(CAST(oif.cancelled AS int)) = COUNT(*);