TSQL一個從2條件選擇行

Question

我有一個表像這樣：

ORDER_ID CODE1 CODE2 CODE3 STATUS 
1   '001' 'BIGP' NULL 4 
2   '002' 'BIGP' NULL 1 
3   '001' NULL NULL 6 
4   '002' NULL 'L'  1 

和第二表所示：

ADDRESS_ID ORDER_ID TYPE ADD_DATE  CATEGORY 
1   1   'K1' '2010-01-01' 'CLIENT' 
2   1   'D1' '2010-01-02' 'SYSTEM' 
3   2   'D2' '2010-01-02' 'SYSTEM' 
4   2   'D2' '2010-02-01' 'CLIENT' 

我必須做，如果爲有每一個訂單是什麼：

• 狀態未在（4,6）
• CODE1 = '002'
• （碼2 = null並且CODE3 = NULL）或（在（ 'BIGA'， 'BIGP' 碼2）和CODE3 = NULL）或（碼2 = NULL和CODE3 = 'L'）

我必須選擇一個地址類型爲'D2'或'K1'（D2具有較高的優先級，所以如果有兩個地址一個K1和另一個D2我必須選擇D2）。
如果沒有任何類型爲D2或K1的地址，我必須爲該訂單選擇類別爲「客戶」的最舊地址。

這是我創造：

SELECT TOP 1000 o.order_Id 
       , a.Address_Id 
       , a.Zip 
      --, * 
FROM orders o 
address a 
    ON a.order_Id = o.order_Id 
WHERE 
(a.Type='D2' OR a.Type='K1') 
AND o.Status NOT IN (4, 6) 
AND code1='002' 
AND ((code2 IS NULL AND code3 IS NULL) OR (code2 IN ('BIGA', 'BIGP') AND code3 IS NULL) OR (code2 IS NULL AND code3 = 'L')) 

Answer 1

你可能會採用CROSS APPLY的任務，因爲它允許使用的TOP 1/ORDER BY報表derived table。

SELECT TOP 1000 o.order_Id 
       , a.Address_Id 
       , a.Zip 
      --, * 
FROM orders o 
CROSS APPLY 
(
select TOP 1 
     a.Address_Id, 
     a.Zip 
    from address a 
    WHERE a.order_Id = o.order_Id 
    ORDER BY case a.Type 
       when 'D2' then 1 
       when 'K1' then 2 
       else 3 
      end, 
     a.ADD_DATE 
) a 
WHERE 
o.Status NOT IN (4, 6) 
AND code1='002' 
AND ((code2 IS NULL AND code3 IS NULL) OR (code2 IN ('BIGA', 'BIGP') AND code3 IS NULL) OR (code2 IS NULL AND code3 = 'L')) 

除此之外，你可能會加入以最小的地址類型的派生表每個訂單：

from orders o 
inner join address a 
    ON a.order_Id = o.order_Id 
inner join 
(
    select a.order_id, a.Type, 
     row_number() over (partition by a.order_id 
          order by case a.Type when 'D2' then 1 
                when 'K1' then 2 
                else 3 
             end, 
             a.ADD_DATE) rn 
    from Address a 
    group by a.order_id, a.Type 
) onlyOneAddress 
    on a.order_id = onlyOneAddress.order_id 
and a.type = onlyOneAddress.type 
and onlyOneAddress.rn = 1 

Answer 2

只是[類型]遞減添加的順序，它會顯示在高優先級