Подкорректировать код

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.OracleClient;
 
namespace DBKR
{
    public partial class Form2 : Form
    {
        OracleConnection ConnectionToOracle;
        string connectionString = "DATA SOURCE=localhost:1521/xe;PASSWORD=12345;PERSIST SECURITY INFO=True;USER ID=SYSTEM";
 
        public Form2()
        {''
            InitializeComponent();
            ConnectionToOracle = new OracleConnection(connectionString);
            ConnectionToOracle.Open();
        }
 
 
        private void button1_Click(object sender, EventArgs e)
        {
            string a, b;
            a = textBox1.Text;
            b = richTextBox1.Text;
            OracleCommand cmd = new OracleCommand();
            cmd.CommandText = "INSERT INTO \"questions" "\"VALUES (@a, @b)""";
            cmd.Connection = ConnectionToOracle;
 
        }
    }
        }

    public partial class Form2 : Form
    {
        const string connectionString = "DATA SOURCE=localhost:1521/xe;PASSWORD=12345;PERSIST SECURITY INFO=True;USER ID=SYSTEM";
 
        public Form2()
        {
            InitializeComponent();
        }
 
 
        private void button1_Click(object sender, EventArgs e)
        {
            string a, b;
            a = textBox1.Text;
            b = richTextBox1.Text;
 
            using (OracleConnection ConnectionToOracle = new OracleConnection(connectionString))
            {
                OracleCommand cmd = new OracleCommand();
                cmd.CommandText = "INSERT INTO \"questions\" VALUES (@a, @b)";
                cmd.Connection = ConnectionToOracle;
                cmd.Parameters.AddWithValue("@a", a);
                cmd.Parameters.AddWithValue("@b", b);
 
                ConnectionToOracle.Open();
                cmd.ExecuteNonQuery();
            }
        }
    }