SQL：如何找到日期時間范圍為30分鍾的“ Created_at”列中的數據集記錄？

Question

SELECT t1.depar_date, t1.return_date, t1.orig_air, t1.dest_air, t1.num_pass, count(t1.id) as count_of, 'TRUE' as Hit_Cache
FROM MY_TEST t1
WHERE  t1.created_at BETWEEN t1.created_at AND dateadd(minute, 30, t1.created_at) --t1.created_at > dateadd(DAY, 1, t1.created_at)
GROUP BY t1.depar_date, t1.return_date, t1.orig_air, t1.dest_air, t1.num_pass
HAVING count(t1.id) > 1;

DATEADD無法識別，並引發錯誤。

Answer 1

大寫MINUTE或以小寫形式使用mm：

SELECT t1.depar_date, t1.return_date, t1.orig_air, t1.dest_air,        t1.num_pass, count(t1.id) as count_of, 'TRUE' as Hit_Cache
FROM MY_TEST t1
WHERE  t1.created_at BETWEEN t1.created_at AND dateadd(MINUTE, 30,     t1.created_at) --t1.created_at > dateadd(DAY, 1, t1.created_at)
GROUP BY t1.depar_date, t1.return_date, t1.orig_air, t1.dest_air, t1.num_pass
HAVING count(t1.id) > 1; 

Answer 2

因為您的查詢針對DATEADD()所以我想您正在使用MySQL。

在我看來，您想知道表中每個記錄的半小時內還有多少其他記錄。

因為要比較記錄與記錄，所以需要自聯接操作。 具體來說，您想要這樣的東西

   FROM MY_TEST t1
   JOIN MY_TEST t2 ON something.

這種結構使您看起來好像在查詢兩個不同的表t1和t2 ，即使它們是相同的數據。

我想你的比較會像這樣

  FROM MY_TEST t1
  JOIN MY_TEST t2 
       ON t2.created_at BETWEEN t1.created_at AND t1.created_at + INTERVAL 30 MINUTE

該聯接操作的結果包括表中與ON條件匹配的所有成對的行對的所有組合。 然后，您可以從那對成對的行中進行選擇和總結。

您的其余查詢看起來與您所遇到的問題非常相似。

SELECT t1.depar_date, t1.return_date, t1.orig_air, 
       t1.dest_air, t1.num_pass, count(t1.id) as count_of,
       'TRUE' as Hit_Cache
  FROM MY_TEST t1
  JOIN MY_TEST t2 
       ON t2.created_at BETWEEN t1.created_at AND t1.created_at + INTERVAL 30 MINUTE
 GROUP BY t1.depar_date, t1.return_date, t1.orig_air, t1.dest_air, t1.num_pass
HAVING count(t1.id) > 1;

也許我猜錯了MySQL。 在SQL Server中，您的ON子句將如下所示。

       ON t2.created_at BETWEEN t1.created_at AND DATEADD(MINUTE, 30, t1.created_at)