Npgsql.NpgsqlConnection.BeginTransaction C# (CSharp) Method

        public new NpgsqlTransaction BeginTransaction()
        {
            NpgsqlEventLog.LogMethodEnter(LogLevel.Debug, CLASSNAME, "BeginTransaction");
            return this.BeginTransaction(IsolationLevel.ReadCommitted);
        }

        public void Append(string name, byte[] data, long expectedVersion)
        {
            using (var conn = new NpgsqlConnection(_connectionString))
            {
                conn.Open();
                using (var tx = conn.BeginTransaction())
                {
                    var version = MakeSureLastVersionMatches(name, expectedVersion, conn, tx);

                    const string txt =
                           @"INSERT INTO ES_Events2 (CustomerId, Name, Version, Data)
                                VALUES(:customerId, :name, :version, :data)";

                    using (var cmd = new NpgsqlCommand(txt, conn, tx))
                    {
                        cmd.Parameters.AddWithValue(":name", name);
                        cmd.Parameters.AddWithValue(":version", version+1);
                        cmd.Parameters.AddWithValue(":data", data);
                        cmd.Parameters.AddWithValue(":customerId", customerId);
                        cmd.ExecuteNonQuery();
                    }
                    tx.Commit();
                }
            }
        }