我每天都在BigQuery上用餐.如何查询“最新"消息?一? [英] I have daily tables on BigQuery. How to query the "newest" one?

问题描述

我创建每日表格.如何查询最新"的?

I create daily tables. How to query the "newest" one?

例如，GitHubArchive现在发布每日表格-而不是整体表格(请参阅 /r/bigquery/.../github_archive_changes_monthly_and_daily_tables/).

For example GitHubArchive now publishes daily tables - instead of a monolithic one (see /r/bigquery/.../github_archive_changes_monthly_and_daily_tables/).

推荐答案

要查找最新表，可以使用BigQuery的表查询功能:

To find the latest table, you could use BigQuery's table query functions:

例如，最新的每日GitHub存档表:

For example, the latest daily GitHubArchive table:

SELECT COUNT(*) num_records
FROM TABLE_QUERY(githubarchive:day,
  "table_id IN (
     SELECT table_id FROM githubarchive:day.__TABLES__ 
     ORDER BY creation_time DESC LIMIT 1)")

# 201859

为了最大的方便，您可以将该查询存储为视图以与他人共享.然后要查询最新的表，只需查询视图:

For maximum convenience, you can store that query as a view to share with others. Then to query the latest table, just query the view:

SELECT num_records
FROM [fh-bigquery:public_dump.githubarchive_latest_day]

# 201859

有关表查询功能的更多信息，请参见Jordan对

For more on table query functions, see Jordan's answer to How do I use the TABLE_QUERY() function in BigQuery?.

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