查询给出错误的结果。知道为啥会这样吗？

Posted 2023-03-31

【中文标题】查询给出错误的结果。知道为啥会这样吗？

【英文标题】：Query giving wrong results. Any idea why is this happening?查询给出错误的结果。知道为什么会这样吗？

【发布时间】：2019-03-06 11:14:37

【问题描述】：

尽管在 ETL 管理器中成功运行，但查询没有返回任何行。知道为什么会这样吗？如果您认为前两个临时表可能包含零结果，我可以保证它们不会，因为我已经分别执行了每个部分。

 CREATE TEMPORARY TABLE T1  AS /* This is to get top 1000 address ids which are unique identifiers for addresses in terms of orders frequency which is decided by number of distinct ordering order ids */
    SELECT destination_address_id 
    ,COUNT(DISTINCT ordering_order_id)a
    FROM oe
    where shipment_status = 'DELIVERED'              
    AND delivery_station_code = 'DCH1'
    AND event_day BETWEEN '2018-10-01' AND '2018-12-31'
    AND tracking_id IS NOT NULL
    GROUP BY destination_address_id
    ORDER BY a DESC
    LIMIT 1000
    ;


    CREATE TEMPORARY TABLE T1_2   AS /* This is to get tracking ids corresponding to those top 1000 address ids */
    SELECT DISTINCT destination_address_id
    ,tracking_id
    FROM oe
    WHERE destination_address_id IN (SELECT destination_address_id FROM T1) 
    AND event_day BETWEEN '2018-10-01' AND '2018-12-31'
    AND shipment_status = 'DELIVERED'
    AND delivery_station_code = 'DCH1'
    AND tracking_id IS NOT NULL

    ;
    SELECT DISTINCT lat1
    ,long1
    ,external_address_id destination_address_id
    ,tracking_id
    ,actual_lat
    ,actual_long
    ,ROW_NUMBER() OVER(PARTITION BY tracking_id ORDER BY deliverydate DESC) rn 
    FROM gdd
    WHERE shipment_status_id in (51,'DELIVERED')
    AND tracking_id IN(SELECT tracking_id FROM T1_2)
    AND confidence1 = 'high'
    AND station_code='DCH1'
    AND deliverydate BETWEEN TO_DATE('2018-10-01','YYYY-MM-DD') AND TO_DATE('2018-12-31','YYYY-MM-DD')
    AND actual_lat IS NOT NULL
    AND actual_long IS NOT NULL

【问题讨论】：

您在最终选择中查找为：AND station_code='DCH1' 而您之前选择 AND delivery_station_code = 'DCH1' 这可能是您的问题吗？

都是一样的，只是不同表的列名不同

只需通过依次注释掉每个 where 条件来分解它，直到找到原因（Joakim 可能是正确的）

【参考方案1】：

检查表格之间的意外格式差异。

建议将以下部分表示为 JOIN 而不是 IN 列表。然后您可以暂时将其更改为左连接，以查看是否有 任何行匹配。

你的 SQL：

…
FROM gdd
WHERE shipment_status_id in (51,'DELIVERED')
AND tracking_id IN(SELECT tracking_id FROM T1_2)
…

加入 SQL：

…
FROM gdd
 INNER | LEFT  JOIN T1_2 ON gdd.tracking_id = T1_2.tracking_id
WHERE shipment_status_id in (51,'DELIVERED')
…

【讨论】：

是的，这似乎是问题所在，但不清楚原因。