如何用另一个 table 的信息替换空数据？

Question

Order_ID       ship_state     bill_state
   121            null            CA
   122            WA              IN    
   123            CA              OR
   124            null            FL

我有一个查询（下方）可以返回这些结果（上方）。 Order_ID、Ship_state 和 bill_state 分别在不同的表中。我如何修改我的查询，以便它用相应的 bill_state 填充 null ship_state？一些订单直接运送到账单地址，这使得运送字段为空，因为它们留空。我想生成一份运送到各州的清单。

SELECT  ca.STATE AS ship_state, 
        co.ID, 
        co.CUSTOMER_ID, 
        ca.ADDR_NO, 
        co.SHIP_TO_ADDR_NO, 
        c.STATE AS Bill_state, 
        c.NAME AS Bill_name, 
        ca.NAME AS Ship_name, 
        col.PART_ID, 
        col.ORDER_QTY, 
        ca.COUNTRY AS Ship_Country, 
        c.COUNTRY AS Bill_country, 
        co.ORDER_DATE
FROM dbo.CUST_ORDER_LINE AS col 
FULL OUTER JOIN dbo.CUST_ADDRESS AS ca 
    FULL OUTER JOIN dbo.CUSTOMER AS c 
        INNER JOIN dbo.CUSTOMER_ORDER AS co 
            ON c.ID = co.CUSTOMER_ID 
        ON ca.CUSTOMER_ID = co.CUSTOMER_ID 
        AND ca.ADDR_NO = co.SHIP_TO_ADDR_NO 
        AND ca.CUSTOMER_ID = c.ID 
    ON col.CUST_ORDER_ID = co.ID
WHERE co.ORDER_DATE > '2014-1-1'
  AND co.ID NOT LIKE 'rma%'
ORDER BY co.ID

Answer 1

使用ISNULL函数，

ISNULL(ca.State, c.State) As ship_state

Answer 2

您可以使用COALESCE函数：

在你的SELECT中：

COALESCE(ca.STATE, c.STATE) AS ship_state

如果 ca.STATE 是 NULL，这将 return c.STATE 的值。

如何用另一个 table 的信息替换空数据？

How to replace null data with information from another table?

sql-server-2008