Class: Blazer::Adapters::BigQueryAdapter

Inherits:
BaseAdapter show all
Defined in:
lib/blazer/adapters/bigquery_adapter.rb

Instance Attribute Summary

Attributes inherited from BaseAdapter

#data_source

Instance Method Summary collapse

Methods inherited from BaseAdapter

#cachable?, #cancel, #cohort_analysis_statement, #cost, #explain, #initialize, #reconnect, #supports_cohort_analysis?

Constructor Details

This class inherits a constructor from Blazer::Adapters::BaseAdapter

Instance Method Details

#parameter_binding ⇒ Object

cloud.google.com/bigquery/docs/parameterized-queries



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# File 'lib/blazer/adapters/bigquery_adapter.rb', line 52

def parameter_binding
  :positional
end

#preview_statement ⇒ Object 



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# File 'lib/blazer/adapters/bigquery_adapter.rb', line 42

def preview_statement
  "SELECT * FROM `{table}` LIMIT 10"
end

#quoting ⇒ Object

cloud.google.com/bigquery/docs/reference/standard-sql/lexical#string_and_bytes_literals



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# File 'lib/blazer/adapters/bigquery_adapter.rb', line 47

def quoting
  :backslash_escape
end

#run_statement(statement, comment, bind_params) ⇒ Object 



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# File 'lib/blazer/adapters/bigquery_adapter.rb', line 4

def run_statement(statement, comment, bind_params)
  columns = []
  rows = []
  error = nil

  begin
    results = bigquery.query(statement, params: bind_params)

    # complete? was removed in google-cloud-bigquery 0.29.0
    # code is for backward compatibility
    if !results.respond_to?(:complete?) || results.complete?
      columns = results.first.keys.map(&:to_s) if results.size > 0
      rows = results.all.map(&:values)
    else
      error = Blazer::TIMEOUT_MESSAGE
    end
  rescue => e
    error = e.message
    error = Blazer::VARIABLE_MESSAGE if error.include?("Syntax error: Unexpected \"?\"")
  end

  [columns, rows, error]
end

#schema ⇒ Object 



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# File 'lib/blazer/adapters/bigquery_adapter.rb', line 32

def schema
  table_refs.map do |table_ref|
    {
      schema: table_ref.dataset_id,
      table: table_ref.table_id,
      columns: table_columns(table_ref)
    }
  end
end

#tables ⇒ Object 



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# File 'lib/blazer/adapters/bigquery_adapter.rb', line 28

def tables
  table_refs.map { |t| "#{t.project_id}.#{t.dataset_id}.#{t.table_id}" }
end