Writing Managed User Defined Function using C#


With the integration of the CLR with SQL Server 2005, we can create database objects using modern object-oriented languages like VB.NET and C#.

This article is trying to explain the simple and required steps that are require starting the creation of Manage User Defined Functions using C#.

The Project:

We will create a Visual Studio 2005 database project for the managed Trigger.

Creating the Database project:

Open Microsoft Visual Studio 2005 and create a SQL Server Project.


Adding a database reference:

Now it will ask for a database reference. Add one.

Add a User Defined Function:

Right click on the Project and add a User Defined Function.

The file Function1.cs:

Past following lines to the file Function1.cs.

using System;

using System.Data;

using System.Data.SqlClient;

using System.Data.SqlTypes;

using Microsoft.SqlServer.Server;


public partial class UserDefinedFunctions



    public static SqlInt64 Function1(SqlInt32 a, SqlInt32 b)


        // Put your code here

        // return new SqlString("Hello");

        return (a + b);


Deploy the User Defined Function:

Build the project and then deploy it.

Test the Trigger:

Make sure the clr is enabled with your SQL Server by running the following sql.

sp_configure 'clr enabled', 1;



Now execute the function with two integer parameter.

Function Defined!!!!