在連接的查詢中過濾行

Question

我無法過濾查詢的結果。這是我執行查詢：返回了以下結果

SELECT 
ORE.ID AS OR_ID, 
ORE.INIT_VERSION AS OR_INIT_VERSION, 
ORE.INSERT_DATE AS OR_INSERT_DATE, 
ORE.INIT_DATE AS OR_INIT_DATE, 
ORE.END_DATE AS OR_END_DATE, 
ORE.STATE AS OR_STATE, 
ORE.ACTION_NAME AS OR_ACTION_NAME, 
ORH.STATE_ID AS ORH_STATE_ID, 
ORH.INSERT_DATE AS ORH_INSERT_DATE, 
CS.STATE AS CS_STATE 

FROM ORDER_REQUEST ORE 
INNER JOIN ORDER_REQUEST_HISTORY ORH ON ORH.ORDER_REQUEST_ID = ORE.ID AND ORH.COMPONENT_ID = ORE.ARCH_ID 
INNER JOIN COMPONENT_STATE CS ON CS.ID = ORH.STATE_ID 
WHERE ORE.ARCH_ID = 219934 
AND CS.STATE IN ('CREAZIONE', 'ANNULLATO', 'REVISIONE PIANIFICATA', 'APPROVAZIONE PIANIFICATA', 'APPROVAZIONE RIFIUTATA', 'COMPLETATO', 'COMPLETATA') 

：

OR_ID OR_STATE OR_INIT_DATE OR_ACTION_NAME ORH_STATE_ID OR_END_DATE  CS_STATE ORH_INSERT_DATE  OR_INSERT_DATE   OR_INIT_VERSION 
8821 COMPLETATA 2014-04-07  ATT    111    2014-06-03  COMPLETATA 15-05-2014 12:48:32 07-04-2014 16:49:42  1 
12266 ACQUISITO 2014-06-03  VAR    10018   NULL   CREAZIONE 30-06-2014 18:59:40 03-06-2014 15:53:51  2 
12266 ACQUISITO 2014-06-03  VAR    10018   NULL   CREAZIONE 01-07-2014 12:56:20 03-06-2014 15:53:51  2 

我想以這樣的方式，對於每個OR_ID我只得到與該行進行過濾最大的ORH_INSERT_DATE，即結果的第一行和第三行。 我嘗試了不同的方法，但似乎沒有工作。 特別是我一直在努力，複雜化JOIN：

INNER JOIN ORDER_REQUEST_HISTORY ORH ON ORH.ORDER_REQUEST_ID = ORE.ID AND ORH.COMPONENT_ID = ORE.ARCH_ID AND ORH.INSERT_DATE = (SELECT INSERT_DATE FROM ORDER_REQUEST_HISTORY ORH2 WHERE ORH2.ORDER_REQUEST_ID = ORE.ID) 

但它只返回上述結果的第一行。我也嘗試以相同的方式使WHERE子句複雜化，但它仍然只返回上面結果集的第一行。

有沒有人知道什麼是正確的條款添加？或者我應該通過後續查詢並解決這個問題嗎？

非常感謝提前，

贊布羅塔

Answer 1

您可以使用WITH子句和ROW_NUMBER功能做到這一點，像這樣：

WITH CTE AS 
(
SELECT 
ORE.ID AS OR_ID, 
ORE.INIT_VERSION AS OR_INIT_VERSION, 
ORE.INSERT_DATE AS OR_INSERT_DATE, 
ORE.INIT_DATE AS OR_INIT_DATE, 
ORE.END_DATE AS OR_END_DATE, 
ORE.STATE AS OR_STATE, 
ORE.ACTION_NAME AS OR_ACTION_NAME, 
ORH.STATE_ID AS ORH_STATE_ID, 
ORH.INSERT_DATE AS ORH_INSERT_DATE, 
CS.STATE AS CS_STATE, 
ROW_NUMBER() OVER (PARTITION BY ORE.ID ORDER BY ORH.INSERT_DATE DESC) AS RN 
FROM ORDER_REQUEST ORE 
INNER JOIN ORDER_REQUEST_HISTORY ORH ON ORH.ORDER_REQUEST_ID = ORE.ID AND  ORH.COMPONENT_ID = ORE.ARCH_ID 
INNER JOIN COMPONENT_STATE CS ON CS.ID = ORH.STATE_ID 
WHERE ORE.ARCH_ID = 219934 
AND CS.STATE IN ('CREAZIONE', 'ANNULLATO', 'REVISIONE PIANIFICATA', 'APPROVAZIONE PIANIFICATA', 'APPROVAZIONE RIFIUTATA', 'COMPLETATO', 'COMPLETATA') 
) 

SELECT * 
FROM CTE 
WHERE RN = 1 

的想法是分區的基礎上，OR_ID並找到最大值爲ORH_INSERT_DATE的行。您也可以通過用所需列代替*來只選擇特定列。