# Introduction to connections BigQuery lets you create external connections to query data that's stored outside of BigQuery in Google Cloud services like Cloud Storage or Spanner, or in third-party sources like Amazon Web Services (AWS) or Microsoft Azure. These external connections use the BigQuery Connection API. For example, suppose that you store details about customer orders in Cloud SQL and data about sales in BigQuery, and you want to join the two tables in a single query. You can create a Cloud SQL connection to the external database by using the BigQuery Connection API. With connections, you never send database credentials as [cleartext](https://simple.wikipedia.org/wiki/Cleartext). A connection is encrypted and securely stored in the BigQuery connection service. You can [give users access to connections](https://docs.cloud.google.com/bigquery/docs/working-with-connections#share-connections) by granting them BigQuery connection Identity and Access Management (IAM) roles. ## Connection types BigQuery provides different connection types for the following external data sources: - Amazon Simple Storage Service (Amazon S3) - Apache Spark - Azure Blob Storage - Google Cloud resources such as Gemini Enterprise Agent Platform remote models, remote functions, and BigLake - Spanner - Cloud SQL - AlloyDB for PostgreSQL - SAP Datasphere > [!NOTE] > **Note:** You don't need a connection to query data in [Bigtable](https://docs.cloud.google.com/bigquery/docs/external-data-bigtable) and [Google Drive](https://docs.cloud.google.com/bigquery/docs/external-data-drive). ### Amazon S3 connections To create an Amazon S3 connection with BigQuery Omni, see [Connect to Amazon S3](https://docs.cloud.google.com/bigquery/docs/omni-aws-create-connection). Once you have an existing Amazon S3 connection, you can do the following: - [Create external tables on Amazon S3](https://docs.cloud.google.com/bigquery/docs/omni-aws-create-external-table) - [Query the Amazon S3 data](https://docs.cloud.google.com/bigquery/docs/query-aws-data) - [Export results to Amazon S3](https://docs.cloud.google.com/bigquery/docs/omni-aws-export-results-to-s3) - [Create datasets based on AWS Glue databases](https://docs.cloud.google.com/bigquery/docs/glue-federated-datasets). ### Spark connections [Stored procedures for Spark](https://docs.cloud.google.com/bigquery/docs/spark-procedures) let you run stored procedures written in Python using BigQuery. A [Spark connection](https://docs.cloud.google.com/bigquery/docs/connect-to-spark) lets you connect to Managed Service for Apache Spark and run the stored procedures for Spark. To create this connection, see [Create connections](https://docs.cloud.google.com/bigquery/docs/connect-to-spark#create-spark-connection). ### Blob Storage connections To create a Blob Storage connection with BigQuery Omni, see [Connect to Blob Storage](https://docs.cloud.google.com/bigquery/docs/omni-azure-create-connection). Once you have an existing Blob Storage connection, you can do the following: - [Create external tables based on Blob Storage](https://docs.cloud.google.com/bigquery/docs/omni-azure-create-external-table) - [Query the Blob Storage data](https://docs.cloud.google.com/bigquery/docs/query-azure-data) - [Export results to Blob Storage](https://docs.cloud.google.com/bigquery/docs/omni-azure-export-results-to-azure-storage) ### Google Cloud resource connections A Google Cloud resource connection is a connection to authorize access to other Google Cloud resources such as Agent Platform remote models, remote functions, and BigLake. For details on how to set up a Google Cloud resource connection, see [Create and set up a Cloud resource connection](https://docs.cloud.google.com/bigquery/docs/create-cloud-resource-connection). Once you have an existing Google Cloud resource connection, you can create the following BigQuery objects with it: - **Remote models** . For more information, see [The CREATE MODEL statement for remote models over LLMs](https://docs.cloud.google.com/bigquery/docs/reference/standard-sql/bigqueryml-syntax-create-remote-model), [The CREATE MODEL statement for remote models over Cloud AI services](https://docs.cloud.google.com/bigquery/docs/reference/standard-sql/bigqueryml-syntax-create-remote-model-service), and [The CREATE MODEL statement for remote models over Agent Platform-hosted models](https://docs.cloud.google.com/bigquery/docs/reference/standard-sql/bigqueryml-syntax-create-remote-model-https). - **Remote functions** . BigQuery [remote functions](https://docs.cloud.google.com/bigquery/docs/remote-functions) let you implement functions with any supported languages in Cloud Run functions or Cloud Run. A remote function connection lets you connect with Cloud Run functions or Cloud Run and run these functions. To create a BigQuery remote function connection, see [Create a connection](https://docs.cloud.google.com/bigquery/docs/remote-functions#create_a_connection). - **BigLake tables** . BigLake connections connect [BigLake tables](https://docs.cloud.google.com/bigquery/docs/biglake-intro) to external data sources while retaining fine-grained BigQuery access control and security for both structured and unstructured data in Cloud Storage. - **Object tables** . For more information, see [Introduction to object tables](https://docs.cloud.google.com/bigquery/docs/object-table-introduction). ### Spanner connections To create a Spanner connection, see [Connect to Spanner](https://docs.cloud.google.com/bigquery/docs/connect-to-spanner). Once you have an existing Spanner connection, you can run [federated queries](https://docs.cloud.google.com/bigquery/docs/federated-queries-intro). ### Cloud SQL connections To create a Cloud SQL connection, see [Connect to Cloud SQL](https://docs.cloud.google.com/bigquery/docs/connect-to-sql). Once you have an existing Cloud SQL connection, you can run [federated queries](https://docs.cloud.google.com/bigquery/docs/federated-queries-intro). ### AlloyDB connections To create an AlloyDB connection, see [Connect to AlloyDB for PostgreSQL](https://docs.cloud.google.com/bigquery/docs/connect-to-alloydb). Once you have an existing AlloyDB connection, you can run [federated queries](https://docs.cloud.google.com/bigquery/docs/federated-queries-intro). ### SAP Datasphere connections > [!WARNING] > > **Preview** > > > This product or feature is > > subject to the "Pre-GA Offerings Terms" in the General Service Terms section > of the [Service Specific > Terms](https://docs.cloud.google.com/terms/service-terms#1). > > Pre-GA products and features are available "as is" and might have limited support. > > For more information, see the > [launch stage descriptions](https://cloud.google.com/products/#product-launch-stages). To create an SAP Datasphere connection, see [Connect to SAP Datasphere](https://docs.cloud.google.com/bigquery/docs/connect-to-sap-datasphere). Once you have an existing SAP Datasphere connection, you can run [federated queries](https://docs.cloud.google.com/bigquery/docs/federated-queries-intro). ## Audit logs BigQuery logs usage and management requests about connections. For more information, see [BigQuery audit logs overview](https://docs.cloud.google.com/bigquery/docs/reference/auditlogs). ## What's next - Learn how to [manage connections](https://docs.cloud.google.com/bigquery/docs/working-with-connections). - Learn more about [default connections](https://docs.cloud.google.com/bigquery/docs/default-connections) for your project. - Learn how to [analyze object tables by using remote functions](https://docs.cloud.google.com/bigquery/docs/object-table-remote-function). - Learn how to query stored data: - [Query data stored in Amazon S3](https://docs.cloud.google.com/bigquery/docs/omni-aws-create-external-table). - [Query data stored in Blob Storage](https://docs.cloud.google.com/bigquery/docs/omni-azure-create-external-table). - [Query structured data stored in Cloud Storage](https://docs.cloud.google.com/bigquery/docs/query-cloud-storage-using-biglake#query-biglake-table-bigquery). - [Query unstructured data stored in Cloud Storage](https://docs.cloud.google.com/bigquery/docs/object-tables). - [Query data stored in Spanner](https://docs.cloud.google.com/bigquery/docs/spanner-federated-queries). - [Query data stored in Cloud SQL](https://docs.cloud.google.com/bigquery/docs/cloud-sql-federated-queries). - [Query data stored in AlloyDB](https://docs.cloud.google.com/bigquery/docs/alloydb-federated-queries). - [Query data using remote functions](https://docs.cloud.google.com/bigquery/docs/remote-functions#create_a_remote_function). - [Query unstructured data using remote functions](https://docs.cloud.google.com/bigquery/docs/object-table-remote-function). - [Query data using stored procedures for Apache Spark](https://docs.cloud.google.com/bigquery/docs/spark-procedures). - Learn about [external tables](https://docs.cloud.google.com/bigquery/docs/external-tables).