string sql = @"insert into CustomerDemographics(CustomerTypeID, CustomerDesc, SomeIntColumn, SomeBitColumn, SomeDateColumn)

                values (@CustomerTypeID, @CustomerDesc, @SomeIntColumn, @SomeBitColumn, @SomeDateColumn)";

string customerTypeId = "test";

string customerDesc = "desc";

int? i = null;

bool? bb = null;

DateTime? dt = null;

using (SqlConnection connection = new SqlConnection(ConfigurationSettings.AppSettings["Main.ConnectionString"]))

using (SqlCommand command = new SqlCommand(sql, connection))

{

    connection.Open();

    command.Parameters.Add(new SqlParameter("@CustomerTypeID", customerTypeId));

    command.Parameters.Add(new SqlParameter("@CustomerDesc", customerDesc));

    command.Parameters.Add(new SqlParameter("@SomeIntColumn", i));

    command.Parameters.Add(new SqlParameter("@SomeBitColumn", bb));

    command.Parameters.Add(new SqlParameter("@SomeDateColumn", dt));

    command.ExecuteNonQuery();

}