在两个表javaDB中添加和减去

Question

我在使用SQL添加和减去来自不同表的值时遇到问题，添加和减去工作正常，但它返回INCORRECT值

这是我的查询，从表1（DELIVERIES表）中添加“QUANTITY”，按“CONTAINER_TYPE”分组，与表2（PULLOUT表）相同，我想要第一个表的数量总和为被减去第二个表的数量之和。但我得到并且不正确的数据。

SELECT
CUSTOMER.CUSTOMER_NAME,
DELIVERIES.CONTAINER_TYPE,
COALESCE(SUM(DELIVERIES.QUANTITY), 0) AS TOTAL_DELIVERY,
COALESCE(SUM(PULLOUTS.QUANTITY), 0) AS TOTAL_RETURNS,
COALESCE(SUM(DELIVERIES.QUANTITY), 0) - COALESCE(SUM(PULLOUTS.QUANTITY), 0) AS CUSTOMER_BALANCE
FROM EJPADMIN.CUSTOMER
INNER JOIN DELIVERIES
   ON DELIVERIES.CUSTOMER_ID = CUSTOMER.CUSTOMER_ID
LEFT JOIN PULLOUTS
    ON PULLOUTS.DELIVERY_ID = DELIVERIES.DELIVERY_ID
GROUP BY CUSTOMER.CUSTOMER_NAME, DELIVERIES.CONTAINER_TYPE

伙计们请帮忙。三江源！

DELIVERIES表 PULLOUT表 CUSTOMER TRANSACTION表（不正确的结果）