Public Sub Main()
        Dim connection As New PgSqlConnection("user id=postgres;password=postgres;port=5432;host=localhost;")
        connection.Open()

        Dim oid As Integer = CreateLargeObject(connection)
        WriteToLargeObject(connection, oid)
        ReadFromLargeObject(connection, oid)
        Console.ReadLine()
End Sub

Public Function CreateLargeObject(ByVal connection As PgSqlConnection) As Integer
        Dim lo As New PgSqlLargeObject(connection)
        ' Create a new large object in the database.
        lo.Create()
        Console.WriteLine("Created new large object with OID = {0}", lo.Oid)
        Return lo.Oid
End Function

Public Sub WriteToLargeObject(ByVal connection As PgSqlConnection, ByVal oid As Integer)
        ' All operations with large objects require an active transaction.
        connection.BeginTransaction()
        Dim str As String = "Hello, world!"
        Dim lo As New PgSqlLargeObject(connection, oid)
        lo.Open()
        If lo.CanWrite Then
                Dim buffer As Byte() = Encoding.UTF8.GetBytes(str)
                lo.Write(buffer, 0, buffer.Length)
        End If
        lo.Close()
        Console.WriteLine("Written to the large object : {0}", str)
        connection.Commit()
End Sub

Public Sub ReadFromLargeObject(ByVal connection As PgSqlConnection, ByVal oid As Integer)
        ' All operations with large objects require an active transaction.
        connection.BeginTransaction()
        Dim str As String = String.Empty
        Dim lo As New PgSqlLargeObject(connection, oid)
        lo.Open()
        If lo.CanWrite Then
                Dim buffer As Byte() = New Byte(lo.Length - 1) {}
                lo.Read(buffer, 0, buffer.Length)
                str = Encoding.UTF8.GetString(buffer)
        End If
        lo.Close()
        Console.WriteLine("Read from the large object : {0}", str)
        connection.Commit()
End Sub