Connect Using the SAP HANA .NET Core Interface

The first step is to check if you have the .NET Core SDK installed and what version it is. Enter the following command:

dotnet --version  

If the dotnet command is not recognized, it means that the .NET Core SDK has not been installed. If the SDK is installed, the command returns the currently installed version, such as 3.1.202.

If the .NET Core SDK is not installed, download it from Download .NET and run the installer on Microsoft Windows or Mac.

Note: Select the ‘Build Apps: Download .NET Core SDK’ option.

On Linux, follow the instructions for the appropriate Linux version such as openSUSE 15 Package Manager - Install .NET Core.

In order for the shell to recognize that the .NET Core SDK is installed and for any dotnet commands in future steps to be recognized, a new shell window needs to be opened.

For further details on supported versions, see SAP Note 2939501 - SAP HANA Client Supported Platforms for 2.5 and later.

1. Create a new console app with the below commands:

   cd %HOMEPATH%/HANAClientsTutorial
   dotnet new console -o dotNET
   

   On Linux or Mac, you need to modify the HDBDOTNETCORE variable to point to the location of the libadonetHDB.so or libadonetHDB.dylib file before creating a new console app. There are two ways to set an environment variable.

   You can either set it using the export command on a Shell window or in a user’s profile script. When an environment variable is modified from the Shell, its existence ends when the user’s sessions ends. This could become an issue when you want the variable to persist across multiple user sessions.

   Hence, choose the second option to set HDBDOTNETCORE.

   Open an editor to edit the file .bash_profile or .profile.

   pico ~/.bash_profile
   

   Replace pico with your preferred text editor.

   Add the following line to it.

   export HDBDOTNETCORE=/home/dan/sap/hdbclient/dotnetcore
   

   Run the source command to immediately apply all the changes made to the .bash_profile file

   source ~/.bash_profile
   

   Now, you may run the following command to create the console app.

   cd $HOME/HANAClientsTutorial
   dotnet new console -o dotNET
   

2. Open the dotNET.csproj file:

   cd dotNET
   notepad dotNET.csproj
   

   cd dotNET
   pico dotNET.csproj
   

   Add the following below the PropertyGroup section (within the Project section) to indicate where to load the SAP HANA Client .NET Core driver from. Modify the HintPath section with the information about where the dll is located on your machine.

   <ItemGroup>
     <Reference Include="Sap.Data.Hana.Core.v2.1">
       <HintPath>C:\SAP\hdbclient\dotnetcore\v2.1\Sap.Data.Hana.Core.v2.1.dll</HintPath>
     </Reference>
   </ItemGroup>
   

   <ItemGroup>
     <Reference Include="Sap.Data.Hana.Core.v2.1">
       <HintPath>/home/dan/sap/hdbclient/dotnetcore/v2.1/Sap.Data.Hana.Core.v2.1.dll</HintPath>
     </Reference>
   </ItemGroup>
   

   

   Once the dotNet.csproj file has been updated, save and close the file.

   The SAP HANA Client interface for .NET Core is compatible with version 2.1, and 3.x releases of .NET Core.

3. Open an editor to edit the file Program.cs.

   notepad Program.cs
   

   pico Program.cs
   

4. Replace the entire contents of Program.cs with the code below:

   using System;
   using Sap.Data.Hana;
   namespace dotNETQuery
   {
   class Program
   {
       static void Main(string[] args)
       {
           try
           {
               // User1UserKey retrieved from hdbuserstore contains server:port, UID and PWD
               // encrypt and sslValidateCertificate should be true for HANA Cloud connections
               // sslValidateCertificate should be set to false when connecting
               // to an SAP HANA, express edition instance that uses a self-signed certificate.
               // As of SAP HANA Client 2.6, connections on port 443 enable encryption by default
               // If hdbuserstore is not used to retrieve the connection information, the format would be
               // "Server=10.7.168.11:39015;UID=User1;PWD=Password1;encrypt=true;sslValidateCertificate=false"
   
               using (var conn = new HanaConnection("key=User1UserKey;encrypt=true;sslValidateCertificate=false"))
               {
                   conn.Open();
                   Console.WriteLine("Connected");
                   var query = "SELECT TITLE, FIRSTNAME, NAME FROM HOTEL.CUSTOMER";
                   using (var cmd = new HanaCommand(query, conn))
                   using (var reader = cmd.ExecuteReader())
                   {
                       Console.WriteLine("Query result:");
                       // Print column names
                       var sbCol = new System.Text.StringBuilder();
                       for (var i = 0; i < reader.FieldCount; i++)
                       {
                           sbCol.Append(reader.GetName(i).PadRight(20));
                       }
                       Console.WriteLine(sbCol.ToString());
                       // Print rows
                       while (reader.Read())
                       {
                           var sbRow = new System.Text.StringBuilder();
                           for (var i = 0; i < reader.FieldCount; i++)
                           {
                               sbRow.Append(reader[i].ToString().PadRight(20));
                           }
                           Console.WriteLine(sbRow.ToString());
                       }
                       conn.Close();
                   }
               }
           }
           catch (Exception ex)
           {
               Console.WriteLine("Error - " + ex.Message);
               Console.WriteLine(ex.ToString());
           }
       }
   }
   }
   

   Save and close the Program.cs file after replacing the code.

   Note that the address, port, UID and PWD will be retrieved from the hdbuserstore.

   The above app makes use of some of the SAP HANA client .NET Core driver methods, such as HanaConnection. Connection details for this class can be found at Microsoft ADO.NET Connection Properties. Further .NET Core API details can be found in the .NET API browser.

5. Run the app:

   dotnet run
   

   Before running the program make sure to be in the directory where Program.cs is saved