BigQuery从专案中的所有表格中选取__TABLES__吗？

Question

使用BigQuery，是否可以__TABLES__从项目中的每个数据集中进行选择？我已经尝试过了，SELECT * FROM '*.__TABLES'但是BigQuery不允许这样做。任何帮助将是巨大的，谢谢！

Answer 1

__TABLES__ 语法仅适用于特定数据集，不适用于所有数据集

您可以做的事情如下

#standardSQL
WITH ALL__TABLES__ AS (
  SELECT * FROM `bigquery-public-data.1000_genomes.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.baseball.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.bls.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.census_bureau_usa.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.cloud_storage_geo_index.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.cms_codes.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.common_us.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.fec.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.genomics_cannabis.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.ghcn_d.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.ghcn_m.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.github_repos.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.hacker_news.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.irs_990.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.medicare.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.new_york.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.nlm_rxnorm.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.noaa_gsod.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.open_images.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.samples.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.san_francisco.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.stackoverflow.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.usa_names.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.utility_us.__TABLES__` 
)
SELECT *
FROM ALL__TABLES__

在这种情况下，您需要提前知道数据集列表，可以轻松地通过Datasets: list API或使用相应的bq
ls进行操作

请注意：以上方法仅适用于数据在相同位置的数据集。如果您的数据集的数据位于不同的位置，则需要在两个不同的查询中查询它们

例如：

#standardSQL
WITH ALL_EU__TABLES__ AS (
  SELECT * FROM `bigquery-public-data.common_eu.__TABLES__` UNION ALL
  SELECT * FROM `bigquery-public-data.utility_eu.__TABLES__` 
)
SELECT *
FROM ALL_EU__TABLES__