Python Client for Google BigQuery

|GA| |pypi| |versions|

Querying massive datasets can be time consuming and expensive without the right hardware and infrastructure. Google BigQuery_ solves this problem by enabling super-fast, SQL queries against append-mostly tables, using the processing power of Google's infrastructure.

• Client Library Documentation_
• Product Documentation_

.. |GA| image:: https://img.shields.io/badge/support-GA-gold.svg :target: https://github.com/googleapis/google-cloud-python/blob/main/README.rst#general-availability .. |pypi| image:: https://img.shields.io/pypi/v/google-cloud-bigquery.svg :target: https://pypi.org/project/google-cloud-bigquery/ .. |versions| image:: https://img.shields.io/pypi/pyversions/google-cloud-bigquery.svg :target: https://pypi.org/project/google-cloud-bigquery/ .. _BigQuery: https://cloud.google.com/bigquery/what-is-bigquery .. _Client Library Documentation: https://googleapis.dev/python/bigquery/latest .. _Product Documentation: https://cloud.google.com/bigquery/docs/reference/v2/

Quick Start

In order to use this library, you first need to go through the following steps:

1. Select or create a Cloud Platform project._
2. Enable billing for your project._
3. Enable the Google Cloud BigQuery API._
4. Setup Authentication._

.. _Select or create a Cloud Platform project.: https://console.cloud.google.com/project .. _Enable billing for your project.: https://cloud.google.com/billing/docs/how-to/modify-project#enable_billing_for_a_project .. _Enable the Google Cloud BigQuery API.: https://cloud.google.com/bigquery .. _Setup Authentication.: https://googleapis.dev/python/google-api-core/latest/auth.html

Installation

Install this library in a `virtualenv`_ using pip. `virtualenv`_ is a tool to
create isolated Python environments. The basic problem it addresses is one of
dependencies and versions, and indirectly permissions.

With `virtualenv`_, it's possible to install this library without needing system
install permissions, and without clashing with the installed system
dependencies.

.. _`virtualenv`: https://virtualenv.pypa.io/en/latest/


Supported Python Versions
^^^^^^^^^^^^^^^^^^^^^^^^^
Python >= 3.7

Unsupported Python Versions
^^^^^^^^^^^^^^^^^^^^^^^^^^^
Python == 2.7, Python == 3.5, Python == 3.6.

The last version of this library compatible with Python 2.7 and 3.5 is
`google-cloud-bigquery==1.28.0`.


Mac/Linux
^^^^^^^^^

.. code-block:: console

    pip install virtualenv
    virtualenv <your-env>
    source <your-env>/bin/activate
    <your-env>/bin/pip install google-cloud-bigquery


Windows
^^^^^^^

.. code-block:: console

    pip install virtualenv
    virtualenv <your-env>
    <your-env>\Scripts\activate
    <your-env>\Scripts\pip.exe install google-cloud-bigquery

Example Usage
-------------

Perform a query

.. code:: python

from google.cloud import bigquery

client = bigquery.Client()

# Perform a query.
QUERY = (
    'SELECT name FROM `bigquery-public-data.usa_names.usa_1910_2013` '
    'WHERE state = "TX" '
    'LIMIT 100')
query_job = client.query(QUERY)  # API request
rows = query_job.result()  # Waits for query to finish

for row in rows:
    print(row.name)

Instrumenting With OpenTelemetry

This application uses OpenTelemetry_ to output tracing data from API calls to BigQuery. To enable OpenTelemetry tracing in the BigQuery client the following PyPI packages need to be installed:

.. _OpenTelemetry: https://opentelemetry.io

.. code-block:: console

pip install google-cloud-bigquery[opentelemetry] opentelemetry-exporter-google-cloud

After installation, OpenTelemetry can be used in the BigQuery client and in BigQuery jobs. First, however, an exporter must be specified for where the trace data will be outputted to. An example of this can be found here:

.. code-block:: python

from opentelemetry import trace
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchExportSpanProcessor
from opentelemetry.exporter.cloud_trace import CloudTraceSpanExporter
trace.set_tracer_provider(TracerProvider())
trace.get_tracer_provider().add_span_processor(
    BatchExportSpanProcessor(CloudTraceSpanExporter())
)

In this example all tracing data will be published to the Google Cloud Trace_ console. For more information on OpenTelemetry, please consult the OpenTelemetry documentation_.

.. _OpenTelemetry documentation: https://opentelemetry-python.readthedocs.io .. _Cloud Trace: https://cloud.google.com/trace