xiv Introduction
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annual developer conference. Two years later, also at Google I/O, Jordan was
on hand to announce public availability.
In the intervening time, we have both been active contributors to the design
and implementation of the BigQuery service. The system has grown consider-
ably, both in the number of users as well as what it can do. We’ve also helped
support the product via mailing lists and the BigQuery area on StackOver ow.
We’ve paid close attention to how the product was used, the kinds of problems
that people had, and the interesting applications they found for the technology.
Along the way we built up a collection of cool things you can do using BigQuery:
different techniques, ways of querying, and methods of working around limita-
tions. These tricks and best practices are in this book.
This book doesn’t attempt to replace the online documentation. Instead, it is
a good format to dive deeper into the service and address different audiences,
particularly those familiar with traditional data warehousing products. In addi-
tion, this book gives you a sense of how BigQuery works and answers some of
the “whys” behind the design.
Although BigQuery, as a product, moves quickly, we’ve written the book
with changes (expected and otherwise) in mind. A new version of BigQuery is
released every week or so, and each one xes bugs, adds features, or improves
scalability and performance. By the time you read this book, BigQuery may
have undergone signi cant evolution.
The BigQuery team works hard at making sure all changes to BigQuery will
be backward compatible. When new functionality is introduced that con icts
with existing behavior, the policy is to ensure the old version continues to work
for at least 12 months. The code and examples in this book should continue to
work for a considerable amount of time. Both code and SQL queries that were
written to interact with BigQuery at the public launch in 2012 still work today.
Even though the BigQuery service maintains backward compatibility, the best
way to achieve a particular result sometimes changes as new features become
available. We have chosen to document in this book core concepts that are useful
independent of details that might change over time. When in doubt, consult the
of cial documentation at https://developers.google.com/bigquery.
Moreover, this book describes integration with other technologies, such as
R, Microsoft Excel, and Tableau. Although each of these technologies is also
evolving, we’ve tried to include things that will likely continue to work for the
foreseeable future. For instance, Chapter 13, “Using BigQuery from Third-Party
Tools,” describes using BigQuery via an ODBC connection. Although each
version of Microsoft Windows may change the user interface slightly around
setting up an ODBC connection, ODBC is a stable technology that will still
work years down the road.
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