日期之间的左联接匹配
Posted
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了日期之间的左联接匹配相关的知识，希望对你有一定的参考价值。
我正在尝试将国定假日的日期与时间段边界配对。我想加入反对buckets的行列。因此，我可以确定假期是否在特定时间范围内has_holiday。
通过以下查询，我收到查询错误：
Query error: LEFT OUTER JOIN cannot be used without a condition that is an equality of fields from both sides of the join. at [6:1]
解决此问题的最佳方法是什么？
DECLARE now_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP();
DECLARE end_date TIMESTAMP DEFAULT TIMESTAMP_SUB(now_date, INTERVAL 365 DAY);
DECLARE block ARRAY<TIMESTAMP> DEFAULT GENERATE_TIMESTAMP_ARRAY(end_date, now_date, INTERVAL 7 DAY);
---------------------------------------------------------------------
WITH buckets AS(
SELECT
TIMESTAMP_SUB(bucket_end, INTERVAL 7 DAY) AS bucket_start,
bucket_end
FROM
UNNEST(block) AS bucket_end
)
SELECT
bucket_start,
bucket_end,
IF(holiday_name IS NOT NULL, 1, 0) AS has_holiday
FROM
buckets AS b
LEFT JOIN
`external_landing.tbl_public_holidays_2020` AS ex
ON
ex.date BETWEEN bucket_start AND bucket_end
external_landing.tbl_public_holidays_2020的表结构
| | day | date | holiday_name | type |
|---:|:----------|:--------------------|:--------------------------------|:---------------------|
| 0 | Tuesday | 2019-01-01 00:00:00 | New Year's Day | National Holiday |
| 1 | Wednesday | 2019-01-02 00:00:00 | Day after New Year's Day | National Holiday |
| 2 | Monday | 2019-01-21 00:00:00 | Wellington Anniversary Day | Regional Holiday |
| 3 | Monday | 2019-01-28 00:00:00 | Auckland Anniversary Day | Regional Holiday |
| 4 | Monday | 2019-02-04 00:00:00 | Nelson Anniversary Day | Regional Holiday |
| 5 | Wednesday | 2019-02-06 00:00:00 | Waitangi Day | National Holiday |
| 6 | Monday | 2019-03-11 00:00:00 | Taranaki Anniversary Day | Regional Holiday |
| 7 | Monday | 2019-03-25 00:00:00 | Otago Anniversary Day | Regional Holiday |
| 8 | Friday | 2019-04-19 00:00:00 | Good Friday | National Holiday |
| 9 | Monday | 2019-04-22 00:00:00 | Easter Monday | National Holiday |
| 10 | Tuesday | 2019-04-23 00:00:00 | Southland Anniversary Day | Regional Holiday |
| 11 | Thursday | 2019-04-25 00:00:00 | Anzac Day | National Holiday |
| 12 | Sunday | 2019-05-12 00:00:00 | Mother's Day | Not A Public Holiday |
| 13 | Monday | 2019-06-03 00:00:00 | Queen's Birthday | National Holiday |
| 14 | Sunday | 2019-09-01 00:00:00 | Father's Day | Not A Public Holiday |
| 15 | Monday | 2019-09-23 00:00:00 | South Canterbury Day | Regional Holiday |
| 16 | Friday | 2019-10-25 00:00:00 | Hawke's Bay Anniversary Day | Regional Holiday |
| 17 | Monday | 2019-10-28 00:00:00 | Labour Day | National Holiday |
| 18 | Monday | 2019-11-04 00:00:00 | Marlborough Anniversary Day | Regional Holiday |
| 19 | Friday | 2019-11-15 00:00:00 | Christchurch Show Day | Regional Holiday |
| 20 | Monday | 2019-12-02 00:00:00 | Chatham Islands Anniversary Day | Regional Holiday |
| 21 | Monday | 2019-12-02 00:00:00 | Westland Anniversary Day | Regional Holiday |
| 22 | Wednesday | 2019-12-25 00:00:00 | Christmas Day | National Holiday |
| 23 | Thursday | 2019-12-26 00:00:00 | Boxing Day | National Holiday |
答案
尝试以下（BigQuery标准SQL）
DECLARE now_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP();
DECLARE end_date TIMESTAMP DEFAULT TIMESTAMP_SUB(now_date, INTERVAL 365 DAY);
DECLARE block ARRAY<TIMESTAMP> DEFAULT GENERATE_TIMESTAMP_ARRAY(end_date, now_date, INTERVAL 7 DAY);
---------------------------------------------------------------------
WITH buckets AS(
SELECT TIMESTAMP_SUB(bucket_end, INTERVAL 7 DAY) AS bucket_start, bucket_end
FROM UNNEST(block) AS bucket_end
)
SELECT
bucket_start,
bucket_end,
IF(holiday_name IS NOT NULL, 1, 0) AS has_holiday
FROM buckets AS b
cross JOIN `external_landing.tbl_public_holidays_2020` AS ex
WHERE ex.date BETWEEN bucket_start AND bucket_end
以上是关于日期之间的左联接匹配的主要内容，如果未能解决你的问题，请参考以下文章