从google.cloud导入bigquery

Question

我正在使用Google BigQuery Ruby Client v0.23并尝试使用参数化查询。我正在关注API docs以供参考。

当我在没有参数的情况下运行查询时，一切都很好。然而，为了使它们动态，当我使用数组参数时，我得到错误。例如。当我运行此查询时

bigquery.query("SELECT COUNT(*) FROM oven.sensor_counts WHERE _PARTITIONTIME = TIMESTAMP('2016-04-04') AND sensor_id IN (@sensor_ids)", params: { sensor_ids: ['48-6', '48-2'] })

我明白了

#<Harley::Response POST https://www.googleapis.com/bigquery/v2/projects/sensors-160421/queries == 400 (413 bytes) 3458ms>
Caught error invalidQuery: No matching signature for operator IN for argument types STRING and {ARRAY<STRING>} at [1:116]
Error - #<Google::Apis::ClientError: invalidQuery: No matching signature for operator IN for argument types STRING and {ARRAY<STRING>} at [1:116]>

Google::Cloud::InvalidArgumentError: invalidQuery: No matching signature for operator IN for argument types STRING and {ARRAY<STRING>} at [1:116]
from /usr/local/var/rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/google-cloud-bigquery-0.23.0/lib/google/cloud/bigquery/service.rb:662:in `rescue in execute'

非常感谢任何见解。

Answer 1

我认为数组只是一个不正确的参数。根据{{3}}，语法为：

x IN (y, z, ...)

请注意，没有数组。

用一个字符串替换数组有效：

require "google/cloud/bigquery"

bigquery = Google::Cloud::Bigquery.new

sql = "SELECT word, SUM(word_count) AS word_count " \
      "FROM `bigquery-public-data.samples.shakespeare`" \
      "WHERE word IN (@words) GROUP BY word"
data = bigquery.query sql, params: { words: 'you' }
#=> [{"word"=>"you", "word_count"=>12527}]

根据上面链接的语法指南，数组参数可以添加UNNEST：

UNNEST表单在FROM子句中处理类似UNNEST的数组扫描：

x [NOT] IN UNNEST(<array expression>)

此表单通常与ARRAY参数一起使用。例如：

x IN UNNEST(@array_parameter)

所以解决方案是：

require "google/cloud/bigquery"

bigquery = Google::Cloud::Bigquery.new

sql = "SELECT word, SUM(word_count) AS word_count " \
      "FROM `bigquery-public-data.samples.shakespeare`" \
      "WHERE word IN UNNEST(@words) GROUP BY word"
data = bigquery.query sql, params: { words: ['me', 'I', 'you'] }
#=> [{"word"=>"I", "word_count"=>21028}, {"word"=>"me", "word_count"=>8030}, {"word"=>"you", "word_count"=>12527}]

Answer 2

还有一种更好的方法，可以使用数组using parameterized approach

从google.cloud导入bigquery

client = bigquery.Client（）

sql =“从烤箱。传感器计数中选择COUNT（*）WHERE _PARTITIONTIME =   TIMESTAMP（'2016-04-04'）AND sensor_id IN UNNEST（@sensor_ids）“

query_params = [       bigquery.ArrayQueryParameter（“ sensor_ids”，“ STRING”，['48 -6'，'48 -2']），]

job_config = bigquery.QueryJobConfig（）job_config.query_parameters =   query_params query_job = client.query（       查询，       job_config = job_config，）client.query（sql，job_config = query_config）

对于参数类型STRING和{ARRAY <string>}（Google BigQuery），运算符IN没有匹配的签名

2 个答案:

从google.cloud导入bigquery

client = bigquery.Client（）