「Teradata的第一個訂單」

Question

我在將SQL語句從Oracle轉換爲Teradata時遇到問題。在Oracle的聲明是這樣的：

SELECT ar.account_no, 
MAX (ah.bal_acct) KEEP (DENSE_RANK FIRST ORDER BY ah.created_t desc) 
FROM ar 
    JOIN ah ON ah.obj_id0 = ar.poid_Id0 
    JOIN acc ON a.poid_id0 = ar.account_obj_Id0 
WHERE acc.account_no = '1234' 
AND ah.created_t <= 1434753495 
GROUP BY ar.account_no 

我需要在Teradata中做類似的聲明。我試着用

QUALIFY ROW_NUMBER() OVER(PARTITION BY max(ah.bal_acct) ORDER BY ah.created_t desc) = 1 

的東西，但是所有的時間我有錯誤：選擇非集合值必須是關聯組的一部分。

這是我得到：

Select ar.account_no, ah.created_t, ah.bal_acct 
FROM VD_REPLICA_BRM.pi_tp_acct_ar_t ar 
    JOIN VD_REPLICA_BRM.pi_tp_acct_ar_hist_T ah ON ah.obj_id0 = ar.poid_Id0 
    JOIN VD_REPLICA_BRM.pi_account_t acc ON acc.poid_id0 = ar.account_obj_Id0 
WHERE acc.account_no = '00003095660515' 
    AND ah.created_t <= CAST('2016-10-31' AS DATE FORMAT 'YYYY-MM-DD') 
QUALIFY ROW_NUMBER() OVER(PARTITION BY max(ah.bal_acct) ORDER BY ah.created_t desc) = 1 
GROUP BY ar.account_no 

我在哪裏都錯了嗎？

Answer 1

我不確定你是否可以用qualify來做到這一點。等同的說法是：

SELECT ar.account_no, ah.created_t, ah.bal_acct 
FROM (SELECT ar.account_no, ah.created_t, ah.bal_acct, 
      ROW_NUMBER() OVER (PARTITION BY ar.account_no ORDER BY ah.created_t DESC) as seqnum 
     FROM ar JOIN 
      ah 
      ON ah.obj_id0 = ar.poid_Id0 JOIN 
      acc 
      ON a.poid_id0 = ar.account_obj_Id0 
     WHERE acc.account_no = '1234' AND ah.created_t <= 1434753495 
    ) t 
WHERE seqnum = 1; 

Duh。你可以用QUALIFY來做到這一點。問題是：GROUP BY：

SELECT ar.account_no, ah.created_t, ah.bal_acct 
FROM VD_REPLICA_BRM.pi_tp_acct_ar_t ar JOIN 
    VD_REPLICA_BRM.pi_tp_acct_ar_hist_T ah 
    ON ah.obj_id0 = ar.poid_Id0 JOIN 
    VD_REPLICA_BRM.pi_account_t acc 
    ON acc.poid_id0 = ar.account_obj_Id0 
WHERE acc.account_no = '00003095660515' AND 
     ah.created_t <= CAST('2016-10-31' AS DATE FORMAT 'YYYY-MM-DD') 
QUALIFY ROW_NUMBER() OVER(PARTITION BY ar_account_no ORDER BY ah.created_t desc) = 1