The file DemoProgram.cs is a demonstration program written in C# which outlines typical, very basic usage scenarios with CrateDB.

CrateDB versions prior to 4.2 needed a custom fork of the official Npgsql .NET data provider for PostgreSQL, crate-npgsql. CrateDB versions 4.2 and later work with the vanilla Npgsql - .NET Access to PostgreSQL driver without the need for a plugin.

The example program in this folder is validated on .NET 8 and 9, using Npgsql 8.x and 9.x.

To invoke a CrateDB instance for evaluation purposes, run:

docker run -it --rm --publish=4200:4200 --publish=5432:5432 crate:latest

Invoke example program:

dotnet run

To connect to CrateDB Cloud, use a command like:

dotnet run -- \
    --host=clustername.aks1.westeurope.azure.cratedb.net --ssl-mode=Require \
    --username=foobar --password='X8F%Shn)TESTvF5ac7%eW4NM'

Explore all available connection options:

dotnet run -- --help

For running the test scenarios wrapped into a xUnit test suite, invoke:

dotnet test

To generate a Cobertura code coverage report, run:

dotnet test --collect:"XPlat Code Coverage"

For running the tests against a remote database, use, for example:

export CRATEDB_DSN='Host=clustername.aks1.westeurope.azure.cratedb.net;Port=5432;SSL Mode=Require;Username=foobar;Password=X8F%Shn)TESTvF5ac7%eW4NM;Database=testdrive'
dotnet test

For running tests selectively, use:

dotnet test --filter SystemQueryExample

If you observe an error like this when invoking the program or test case:

Microsoft.PackageDependencyResolution.targets(266,5): error NETSDK1005:
Assets file '/path/to/csharp-npgsql/obj/project.assets.json' doesn't have a target for 'net9.0'.
Ensure that restore has run and that you have included 'net9.0' in the TargetFrameworks for your project.

please adjust demo.csproj like that:

-    <TargetFramework>net$(NETCoreAppMaximumVersion)</TargetFramework>

• <TargetFrameworks>net6.0;net8.0;net9.0</TargetFrameworks>