.NET Database Connection Examples

To connect to a database, an SAConnection object must be created. The connection string can be specified when creating the object or it can be established later by setting the ConnectionString property.

A well-designed application should handle any errors that occur when attempting to connect to a database.

A connection to the database is created when the connection is opened and released when the connection is closed.

C# SAConnection example

The following C# code creates a button click handler that opens a connection to the SAP Sybase IQ sample database and then closes it. An exception handler is included.

private void button1_Click(object sender, EventArgs e)
{
    SAConnection conn = new SAConnection("Data Source=Sybase IQ Demo");
    try
    {
        conn.Open();

        conn.Close();
    }
    catch (SAException ex)
    {
        MessageBox.Show(ex.Errors[0].Source + " : " +
             ex.Errors[0].Message + " (" +
             ex.Errors[0].NativeError.ToString() + ")",
             "Failed to connect");
    }
}

Visual Basic SAConnection example

The following Visual Basic code creates a button click handler that opens a connection to the SAP Sybase IQ sample database and then closes it. An exception handler is included.

Private Sub Button1_Click(ByVal sender As System.Object, _
     ByVal e As System.EventArgs) Handles Button1.Click
    Dim conn As New SAConnection("Data Source=Sybase IQ Demo")
    Try
        conn.Open()

        conn.Close()
    Catch ex As SAException
        MessageBox.Show(ex.Errors(0).Source & " : " & _
                 ex.Errors(0).Message & " (" & _
                 ex.Errors(0).NativeError.ToString() & ")", _
                 "Failed to connect")
    End Try
End Sub

Connection Pooling
The SAP Sybase IQ .NET Data Provider supports native .NET connection pooling. Connection pooling allows your application to reuse existing connections by saving the connection handle to a pool so it can be reused, rather than repeatedly creating a new connection to the database. Connection pooling is enabled by default.
Connection State
Once your application has established a connection to the database, you can check the connection state to ensure that the connection is still open before communicating a request to the database server. If a connection is closed, you can return an appropriate message to the user and/or attempt to reopen the connection.

Parent topic: SAP Sybase IQ .NET Data Provider