使用SQL从特定日期选择活动

Question

我想在Stack Overflow问题和答案数据集上查找特定一天提出的问题数。在2018-11-11有多少问题被问到？

how = """SELECT
  EXTRACT(DAY FROM DATE '2018-11-11') AS Day,
  EXTRACT(MONTH FROM DATE '2018-11-11') AS Month,
  EXTRACT(YEAR FROM DATE '2018-11-11') AS Year,
  COUNT(*) AS Number_of_Questions,
  ROUND(100 * SUM(IF(answer_count > 0, 1, 0)) / COUNT(*), 1) AS Percent_Questions_with_Answers
FROM
  `bigquery-public-data.stackoverflow.posts_questions`
GROUP BY
  Day
HAVING
  Day > 0 AND day < 12
ORDER BY
  Day;

    """


how = stackOverflow.query_to_pandas_safe(how)
how.head(12)

我使用的代码检索整个数据集中的所有问题，而不是在我选择的日期。如果我尝试用@@进行过滤，我会得到一个错误

Answer 1

查询不会是这样的吗？

SELECT COUNT(*) AS Number_of_Questions
FROM `bigquery-public-data.stackoverflow.posts_questions`
WHERE DATE = DATE('2018-11-11');

编辑：

我看到这是一个公开的数据集。假设您指的是创建日期，则：

SELECT count(*)
FROM `bigquery-public-data.stackoverflow.posts_questions` pq
WHERE creation_date >= TIMESTAMP('2018-11-11') and
      creation_date < TIMESTAMP('2018-11-12') ;

这段代码是经过测试的，当我运行它时，它可以正常工作。

Answer 2

下面是针对BigQuery标准SQL的说明

#standardSQL
SELECT
  DATE(creation_date) AS day,
  COUNT(*) AS Number_of_Questions,
  ROUND(100 * COUNTIF(answer_count > 0) / COUNT(*), 1) AS Percent_Questions_with_Answers
FROM `bigquery-public-data.stackoverflow.posts_questions` 
WHERE DATE(creation_date) BETWEEN '2018-11-01' AND '2018-11-11'
GROUP BY day
-- ORDER BY day

有结果

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