Impala查询昨天的数据而不键入日期（可能使用python）

数据已被解析为日期时间“2018-03-08 00:00:00”。我可以通过说出“2018-03-08 00:00:00”和“2018-03-08 24:00:00”之间的位置来获得2018年3月8日的数据。但是我想以某种方式使用Impala日期时间函数，这样我就可以每天运行它，而不用手动输入每个日期。我已经阅读了一些文档，但仍然感到困惑

查询黑斑羚 即使我可以在查询之前用python定义昨天，如下所示：

yesterday = str((pd.to_datetime('today') - pd.Timedelta(days=1)).date())

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并以某种方式将其合并到Impala查询中。

您的问题并不完全清楚，但据我所知，您希望使用Impala/python日期时间函数来自动执行查询，以选择一天的数据。下面是我在黑斑羚身上的例子

-- to_date - function will cut the date from timestamp
-- now()   - gives you the current timestamp

select to_date(now()) as currentDate, 
to_date(now() + interval 1 days) as currentDatePlusaDay, 
now() as currentTimestamp, 
now() + interval 1 day as currentTimestampPlusaDay, 
concat(to_date(now() - interval 1 days), ' 00:00:00') as whereBetweenMin, 
concat(to_date(now() - interval 1 days), ' 24:00:00') as whereBetweenMax ;

--Result

+-------------+---------------------+-------------------------------+-------------------------------+---------------------+---------------------+
| currentdate | currentdateplusaday | currenttimestamp              | currenttimestampplusaday      | wherebetweenmin     | wherebetweenmax     |
+-------------+---------------------+-------------------------------+-------------------------------+---------------------+---------------------+
| 2018-03-23  | 2018-03-24          | 2018-03-23 12:14:36.073281000 | 2018-03-24 12:14:36.073281000 | 2018-03-22 00:00:00 | 2018-03-22 24:00:00 |
+-------------+---------------------+-------------------------------+-------------------------------+---------------------+---------------------+

--You can probably use wherebetweenmin & wherebetweenmax

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从表中选择子字符串（时间，1,10）作为日期字符串，子字符串（时间，12,2）作为小时字符串，count（*）作为countString，其中concat（到日期（现在（）-间隔5天），“00:00:00”）和concat（到日期（现在（）-间隔5天），“24:00:00”）之间的时间按子字符串（时间，1,10）分组，子字符串（时间，12,2）以1,2的顺序排列@roh@sectechguy如果这个答案是你问题的解决方案，那么你应该接受它。

-- to_date - function will cut the date from timestamp
-- now()   - gives you the current timestamp

select to_date(now()) as currentDate, 
to_date(now() + interval 1 days) as currentDatePlusaDay, 
now() as currentTimestamp, 
now() + interval 1 day as currentTimestampPlusaDay, 
concat(to_date(now() - interval 1 days), ' 00:00:00') as whereBetweenMin, 
concat(to_date(now() - interval 1 days), ' 24:00:00') as whereBetweenMax ;

--Result

+-------------+---------------------+-------------------------------+-------------------------------+---------------------+---------------------+
| currentdate | currentdateplusaday | currenttimestamp              | currenttimestampplusaday      | wherebetweenmin     | wherebetweenmax     |
+-------------+---------------------+-------------------------------+-------------------------------+---------------------+---------------------+
| 2018-03-23  | 2018-03-24          | 2018-03-23 12:14:36.073281000 | 2018-03-24 12:14:36.073281000 | 2018-03-22 00:00:00 | 2018-03-22 24:00:00 |
+-------------+---------------------+-------------------------------+-------------------------------+---------------------+---------------------+

--You can probably use wherebetweenmin & wherebetweenmax