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Google Cloud BigQuery C++ Client Library

This directory contains an idiomatic C++ client library for interacting with Cloud BigQuery.

While this library is GA, please note that the Google Cloud C++ client libraries do not follow Semantic Versioning.

Supported Platforms

  • Windows, macOS, Linux
  • C++14 (and higher) compilers (we test with GCC >= 7.3, Clang >= 6.0, and MSVC >= 2017)
  • Environments with or without exceptions
  • Bazel (>= 4.0) and CMake (>= 3.5) builds

Documentation

Quickstart

The quickstart/ directory contains a minimal environment to get started using this client library in a larger project. The following "Hello World" program is used in this quickstart, and should give you a taste of this library.

#include "google/cloud/bigquery/bigquery_read_client.h"
#include <iostream>

namespace {
void ProcessRowsInAvroFormat(
    ::google::cloud::bigquery::storage::v1::AvroSchema const&,
    ::google::cloud::bigquery::storage::v1::AvroRows const&) {
  // Code to deserialize avro rows should be added here.
}
}  // namespace

int main(int argc, char* argv[]) try {
  if (argc != 3) {
    std::cerr << "Usage: " << argv[0] << " <project-id> <table-name>\n";
    return 1;
  }

  // project_name should be in the format "projects/<your-gcp-project>"
  std::string const project_name = "projects/" + std::string(argv[1]);
  // table_name should be in the format:
  // "projects/<project-table-resides-in>/datasets/<dataset-table_resides-in>/tables/<table
  // name>" The project values in project_name and table_name do not have to be
  // identical.
  std::string const table_name = argv[2];

  // Create a namespace alias to make the code easier to read.
  namespace bigquery = ::google::cloud::bigquery;
  constexpr int kMaxReadStreams = 1;
  // Create the ReadSession.
  auto client =
      bigquery::BigQueryReadClient(bigquery::MakeBigQueryReadConnection());
  ::google::cloud::bigquery::storage::v1::ReadSession read_session;
  read_session.set_data_format(
      google::cloud::bigquery::storage::v1::DataFormat::AVRO);
  read_session.set_table(table_name);
  auto session =
      client.CreateReadSession(project_name, read_session, kMaxReadStreams);
  if (!session) throw std::move(session).status();

  // Read rows from the ReadSession.
  constexpr int kRowOffset = 0;
  auto read_rows = client.ReadRows(session->streams(0).name(), kRowOffset);

  std::int64_t num_rows = 0;
  for (auto const& row : read_rows) {
    if (row.ok()) {
      num_rows += row->row_count();
      ProcessRowsInAvroFormat(session->avro_schema(), row->avro_rows());
    }
  }

  std::cout << num_rows << " rows read from table: " << table_name << "\n";
  return 0;
} catch (google::cloud::Status const& status) {
  std::cerr << "google::cloud::Status thrown: " << status << "\n";
  return 1;
}
  • Packaging maintainers or developers who prefer to install the library in a fixed directory (such as /usr/local or /opt) should consult the packaging guide.
  • Developers that prefer using a package manager such as vcpkg, Conda, or Conan should follow the instructions for their package manager.
  • Developers wanting to use the libraries as part of a larger CMake or Bazel project should consult the quickstart guides for the library or libraries they want to use.
  • Developers wanting to compile the library just to run some examples or tests should read the current document.
  • Contributors and developers to google-cloud-cpp should consult the guide to set up a development workstation.

Installation

Please consult the packaging guide for detailed instructions to install the Google Cloud C++ client libraries. If your project uses CMake or Bazel check the quickstart example for instructions to use this library in your project.

Contributing changes

See CONTRIBUTING.md for details on how to contribute to this project, including how to build and test your changes as well as how to properly format your code.

Licensing

Apache 2.0; see LICENSE for details.