如何5分钟时戳间隔转换为1分钟的时间间隔在SQL保持其它的信息？

Question

我看到一个或两个题目问的是相反的（转1分钟时间戳为5分钟或其他时戳间隔）。不过我挺不明白这个节目的想法。

这是我的输入表：

timestamp     Food      Beverage
15:00:00      Pizza      Coke
15:05:00      Burger     Coke
15:10:00      Hotdog     Pepsi
   …             …        …

而这将是我想要的输出：

timestamp   Food    Beverage
 15:00:00   Pizza   Coke
 15:01:00   Pizza   Coke
 15:02:00   Pizza   Coke
 15:03:00   Pizza   Coke
 15:04:00   Pizza   Coke
 15:05:00   Burger  Coke
 15:06:00   Burger  Coke
 15:07:00   Burger  Coke
 15:08:00   Burger  Coke
 15:09:00   Burger  Coke
 15:10:00   Hotdog  Pepsi
 15:11:00   Hotdog  Pepsi
    …         …       …

提前致谢！

Answer 1

最简单的方法是使用cross join：

select dateadd(minute, v.m, timestamp) as timestamp,
       food, beverage
from t cross join
     (values (0), (1), (2), (3), (4)) v(m);

您也可以使用显式select / union all做到这一点：

select dateadd(minute, v.m, timestamp) as timestamp,
       food, beverage
from t cross join
     (select 0 as m union all select 1 union all select 2 union all select 3 union all select 4
     ) v(m);

Answer 2

您可以使用DATEADD。参数输入N表示分钟。

该ROW_NUMBER将增加每行的时间戳。

DECLARE @interval varchar(10) = 5

DROP TABLE IF EXISTS #data

SELECT timestamp='15:00:00',Food='Pizza',Beverage='Coke'
INTO #data
UNION ALL SELECT timestamp='15:05:00',Food='Burger',Beverage='Coke'
UNION ALL SELECT timestamp='15:10:00',Food='Pizza',Beverage='Pepsi'

DROP TABLE IF EXISTS #TAB 
CREATE TABLE #TAB (id int)

EXEC ('INSERT INTO #TAB
SELECT TOP '+@interval+ ' ROW_NUMBER() OVER(ORDER BY name) FROM sys.columns')

SELECT timestamp=CAST(DATEADD(n,ROW_NUMBER() OVER (PARTITION BY timestamp,food,beverage ORDER BY Food),timestamp) as time) , Food,Beverage
FROM #data
CROSS JOIN #TAB
ORDER BY 1

输出将是：

+------------------+--------+----------+
|    timestamp     |  Food  | Beverage |
+------------------+--------+----------+
| 15:01:00.0000000 | Pizza  | Coke     |
| 15:02:00.0000000 | Pizza  | Coke     |
| 15:03:00.0000000 | Pizza  | Coke     |
| 15:04:00.0000000 | Pizza  | Coke     |
| 15:05:00.0000000 | Pizza  | Coke     |
| 15:06:00.0000000 | Burger | Coke     |
| 15:07:00.0000000 | Burger | Coke     |
| 15:08:00.0000000 | Burger | Coke     |
| 15:09:00.0000000 | Burger | Coke     |
| 15:10:00.0000000 | Burger | Coke     |
| 15:11:00.0000000 | Pizza  | Pepsi    |
| 15:12:00.0000000 | Pizza  | Pepsi    |
| 15:13:00.0000000 | Pizza  | Pepsi    |
| 15:14:00.0000000 | Pizza  | Pepsi    |
| 15:15:00.0000000 | Pizza  | Pepsi    |
+------------------+--------+----------+