C# Drivers

• PostgreSQL Npgsql

Npgsql is an open source ADO.NET Data Provider for PostgreSQL, it allows programs written in C#, Visual Basic, F# to access the YugabyteDB server. It is implemented in 100% C# code, is free and is open source.

Quick Start

Learn how to establish a connection to YugabyteDB database and begin simple CRUD operations using the steps in Build an Application in the Quick Start section.

Download the Driver Dependency

If you are using Visual Studio IDE, follow the below steps:

1. Open your Project Solution View
2. Right-click on Packages and click Add Packages
3. Search for Npgsql and click Add Package

To add Npgsql package to your project, when not using an IDE, use the dotnet command:

dotnet add package Npgsql 

or any of the other methods mentioned on the nuget page for Npgsql.

Fundamentals

Learn how to perform the common tasks required for Java App development using the PostgreSQL JDBC driver

Connect to YugabyteDB Database

After setting up the dependenices, we implement the C# client application that uses the Npgsql driver to connect to your YugabyteDB cluster and run query on the sample data.

We will import Npgsql and use the NpgsqlConnection class for getting connection object for the YugabyteDB Database which can be used for performing DDLs and DMLs against the database.

Example URL for connecting to YugabyteDB can be seen below.

var yburl = "host=localhost;port=5433;database=yb_demo;user id=yugabyte;password="
NpgsqlConnection conn = new NpgsqlConnection(yburl);

Create Table

Tables can be created in YugabyteDB by passing the CREATE TABLE DDL statement to the NpgsqlCommand class and getting a command object, then calling the ExecuteNonQuery() method using this command object.

For example

CREATE TABLE employee (id int PRIMARY KEY, name varchar, age int, language varchar)

conn.Open();
NpgsqlCommand empCreateCmd = new NpgsqlCommand("CREATE TABLE employee (id int PRIMARY KEY, name varchar, age int, language varchar);", conn);
empCreateCmd.ExecuteNonQuery();

Read and Write Data

Insert Data

In order to write data into YugabyteDB, execute the INSERT statement using the NpgsqlCommand class and get a command object, then call the ExecuteNonQuery() method using this command object.

For example

INSERT INTO employee (id, name, age, language) VALUES (1, 'John', 35, 'CSharp');

NpgsqlCommand empInsertCmd = new NpgsqlCommand("INSERT INTO employee (id, name, age, language) VALUES (1, 'John', 35, 'CSharp');", conn);
int numRows = empInsertCmd.ExecuteNonQuery();

Query Data

In order to query data from YugabyteDB tables, execute the SELECT statement using NpgsqlCommand class, get the command object and then call the ExecuteReader() function using the object. Loop through the reader to get the list of returned rows.

For example

SELECT * from employee where id=1;

NpgsqlCommand empPrepCmd = new NpgsqlCommand("SELECT name, age, language FROM employee WHERE id = @EmployeeId", conn);
empPrepCmd.Parameters.Add("@EmployeeId", NpgsqlTypes.NpgsqlDbType.Integer);

empPrepCmd.Parameters["@EmployeeId"].Value = 1;
NpgsqlDataReader reader = empPrepCmd.ExecuteReader();

Console.WriteLine("Query returned:\nName\tAge\tLanguage"); 
while (reader.Read())
{
    Console.WriteLine("{0}\t{1}\t{2}", reader.GetString(0), reader.GetInt32(1), reader.GetString(2));
}

Configure SSL/TLS

For Npgsql versions < 6.0, The client driver supports several SSL modes, as follows:

The Npgsql driver does not support the strings verify-ca and verify-full when specifying the SSL mode.

The .NET Npgsql driver validates certificates differently from other PostgreSQL drivers. When you specify SSL mode require, the driver verifies the certificate by default (like the verify-ca or verify-full modes), and fails for self-signed certificates. You can override this by specifying "Trust Server Certificate=true", in which case it bypasses walking the certificate chain to validate trust and hence works like other drivers' require mode. In this case, the Root-CA certificate is not required to be configured.

For versions 6.0 and older,

SSL Mode=Require currently requires explicitly setting Trust Server Certificate=true as well. This combination should be used with e.g. self-signed certificates.

The default mode in 6.0+ is Prefer, which allows SSL but does not require it, and does not validate certificates.

Compatibility Matrix

Other Usage Examples

• SSL Example

FAQ