npgsql

Aurora DSQL with Npgsql

Overview

This code example demonstrates how to use Npgsql with Amazon Aurora SQL (DSQL). The example shows you how to connect to an Aurora DSQL cluster and perform basic database operations.

Aurora DSQL is a distributed SQL database service that provides high availability and scalability for your PostgreSQL-compatible applications. Npgsql is a popular PostgreSQL adapter for .NET that allows you to interact with PostgreSQL databases using C# code.

About the code example

The example demonstrates a flexible connection approach that works for both admin and non-admin users:

• When connecting as an admin user, the example uses the public schema and generates an admin authentication token.
• When connecting as a non-admin user, the example uses a custom myschema schema and generates a standard authentication token.

The code automatically detects the user type and adjusts its behavior accordingly.

⚠️ Important

• Running this code might result in charges to your AWS account.
• We recommend that you grant your code least privilege. At most, grant only the minimum permissions required to perform the task. For more information, see Grant least privilege.
• This code is not tested in every AWS Region. For more information, see AWS Regional Services.

TLS connection configuration

This example uses direct TLS connections where supported, and verifies the server certificate is trusted. Verified SSL connections should be used where possible to ensure data security during transmission.

• Driver versions following the release of PostgreSQL 17 support direct TLS connections, bypassing the traditional PostgreSQL connection preamble
• Direct TLS connections provide improved connection performance and enhanced security
• Not all PostgreSQL drivers support direct TLS connections yet, or only in recent versions following PostgreSQL 17
• Ensure your installed driver version supports direct TLS negotiation, or use a version that is at least as recent as the one used in this sample
• If your driver doesn't support direct TLS connections, you may need to use the traditional preamble connection instead

Run the example

Prerequisites

• You must have an AWS account, and have your default credentials and AWS Region configured as described in the Globally configuring AWS SDKs and tools guide.
• .NET 9.0 SDK or later.
• You must have an Aurora DSQL cluster. For information about creating an Aurora DSQL cluster, see the Getting started with Aurora DSQL guide.
• If connecting as a non-admin user, ensure the user is linked to an IAM role and is granted access to the myschema schema. See the Using database roles with IAM roles guide.

Run the code

The example demonstrates the following operations:

• Opening a connection to an Aurora DSQL cluster
• Creating a table
• Inserting and querying data

The example is designed to work with both admin and non-admin users:

• When run as an admin user, it uses the public schema
• When run as a non-admin user, it uses the myschema schema

Note: running the example will use actual resources in your AWS account and may incur charges.

Set environment variables for your cluster details:

# e.g. "admin"
export CLUSTER_USER="<your user>"

# e.g. "foo0bar1baz2quux3quuux4.dsql.us-east-1.on.aws"
export CLUSTER_ENDPOINT="<your endpoint>"

# e.g. "us-east-1"
export REGION="<your region>"

Run the example:

dotnet run --framework net9.0

The example contains comments explaining the code and the operations being performed.

Additional resources

• Amazon Aurora DSQL Documentation
• Npgsql Documentation

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SPDX-License-Identifier: MIT-0