我想在 Where 条件中输入 2 个日期，一次用于 8 月，一次用于 10 月

Posted 2023-03-24

【中文标题】我想在 Where 条件中输入 2 个日期，一次用于 8 月，一次用于 10 月

【英文标题】：I would like to enter 2 dates in the Where condition, once for August and once for October

【发布时间】：2020-10-19 14:51:59

【问题描述】：

。不幸的是，我在这里没有进一步说明，因为我只能在 Where 条件中输入日期（从 .. 到），请参阅 AND 日期之间。

SELECT
  subregion1_code,
  subregion1_name,
  SUM(new_confirmed) as august_confirmed,
  SUM(new_tested) as august_tested,
  SUM(new_confirmed) as october_confirmed,
  SUM(new_tested) as october_tested,
  SUM(new_confirmed) / SUM(new_tested) AS positive_test_rate, 
FROM
  `bigquery-public-data.covid19_open_data.covid19_open_data` as B
WHERE
  country_code = "US"
  AND aggregation_level = 1
  AND date BETWEEN '2020-10-01' AND '2020-10-30'
 
GROUP BY
  subregion1_code,
  subregion1_name 
ORDER BY
  positive_test_rate DESC

【问题讨论】：

date 是列名吗？

是否总是比您想要的所选日期提前 2 个月？

@Akina 是的

@nbk 不，我想要 8 月的专栏（如 august_confirmed，august_tested）和 10 月的专栏（october_confirmed，october_tested），但应该在一个代码中

【参考方案1】：

您可以使用条件聚合来做到这一点：

SELECT
  subregion1_code,
  subregion1_name,
  SUM(CASE WHEN MONTH(date) = 8 THEN new_confirmed ELSE 0 END) AS august_confirmed,
  SUM(CASE WHEN MONTH(date) = 8 THEN new_tested ELSE 0 END) AS august_tested,
  SUM(CASE WHEN MONTH(date) = 10 THEN new_confirmed ELSE 0 END) AS october_confirmed,
  SUM(CASE WHEN MONTH(date) = 10 THEN new_tested ELSE 0 END) AS october_tested,
  SUM(new_confirmed) / SUM(new_tested) AS positive_test_rate, 
FROM `bigquery-public-data.covid19_open_data.covid19_open_data` AS B
WHERE
  country_code = 'US'
  AND aggregation_level = 1
  AND (date BETWEEN '2020-10-01' AND '2020-10-31' OR date BETWEEN '2020-08-01' AND '2020-08-31')
GROUP BY subregion1_code, subregion1_name 
ORDER BY positive_test_rate DESC

【讨论】：

但这适用于 8 月和 10 月，但我想要 10 月和 9 月的“Where 条件”

我想在 Where 条件中输入 2 个日期，一个是 8 月，一个是 10 月。 九月还是十月？另外：SUM(CASE WHEN MONTH(date) = 8 THEN new_confirmed ELSE 0 END) 仅返回 8 月的总和，SUM(CASE WHEN MONTH(date) = 10 THEN new_confirmed ELSE 0 END) 仅返回 10 月的总和。