Проблемы с обновлением БД

try
            {
                connection = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + @".\AppData\SerialsDB.accdb");
                OleDbCommand myOleDbCommand = connection.CreateCommand();
                OleDbDataAdapter thisAdapter = new OleDbDataAdapter();
                string name = textBox1.Text;
                string url = textBox2.Text;
               
                string command = "UPDATE SerialsBase SET Title =" + name + ", Url =" + url +" WHERE Id =" + (selectedIndex+1) + ")";
                myOleDbCommand.CommandText = command;
 
                connection.Open();
 
                thisAdapter.UpdateCommand = new OleDbCommand(command, connection);
                thisAdapter.UpdateCommand.ExecuteNonQuery();
                connection.Close();
                MessageBox.Show("Запись изменена!!", "Успех", MessageBoxButtons.OK, MessageBoxIcon.Information);
                
                this.Close();
            }
            catch (OleDbException)
            {
                MessageBox.Show("Ошибка записи");
                connection.Close();
            }

string command = "UPDATE SerialsBase SET Title ='" + name + "', Url ='" + url +"' WHERE Id =" + (selectedIndex+1) + ")";

string command = "UPDATE SerialsBase SET Title =" + name + ", Url =" + url +" WHERE Id =" + (selectedIndex+1).ToString();

myOleDbCommand.CommandText = "UPDATE SerialsBase SET Title = @name, Url = @url +  WHERE Id = @selectedIndex";
                myOleDbCommand.Parameters.Add("@name", (OleDbType) SqlDbType.NVarChar, 50);
                myOleDbCommand.Parameters["@name"].Value = name;
                myOleDbCommand.Parameters.Add("@url", (OleDbType)SqlDbType.NVarChar, 150);
                myOleDbCommand.Parameters["@url"].Value = url;
                myOleDbCommand.Parameters.Add("@selectedIndex", (OleDbType)SqlDbType.NVarChar, 150);
                myOleDbCommand.Parameters["@selectedIndex"].Value = (selectedIndex+1).ToString();

thisAdapter.UpdateCommand.ExecuteNonQuery();

 string command = "UPDATE SerialsBase SET Title = '" + name + "', Url ='" + url + "' WHERE id =" + (selectedIndex + 1);
                updateOleDbCommand.CommandText ="UPDATE SerialsBase SET Title = '" + name + "', Url ='" + url + "' WHERE id =" + (selectedIndex+1);
               
                
 
                connection.Open();
                thisAdapter.UpdateCommand = new OleDbCommand(command, connection);
                thisAdapter.UpdateCommand.ExecuteNonQuery();