C#SQL帮助！“插入到”正在覆盖现有数据

我在C#中学习SQL，遇到了一些麻烦。我不知道如何在不覆盖现有数据的情况下将数据插入sql表。

我可以很容易地在表中添加值，我甚至创建了一个方法来填充数据进行测试，并且可以轻松快速地添加500个值，但当我再次运行它时，它会覆盖现有的值，而不是添加到它中。

这是我的代码：

public static void AddSongViaClass(Songs s)
    {
        string conStr = "TestSQL.Properties.Settings.ArtistConnectionString";
        using (SqlConnection sqlcon = new SqlConnection(GetConnectionString(conStr)))
        {
            sqlcon.Open();
            try
            {
                string query = "INSERT INTO Songs (Name, Id, Album, TrackNumber, TrackNumberCount, Genre, Rating, Tags, Subject, Categories, Comments, FileName, FolderName, FolderPath, FullPath, Length, PlayCount, SkipCount, LastPlayed)";
                query += " VALUES (@Name, @Id, @Album, @TrackNumber, @TrackNumberCount, @Genre, @Rating, @Tags, @Subject, @Categories, @Comments, @FileName, @FolderName, @FolderPath, @FullPath, @Length, @PlayCount, @SkipCount, @LastPlayed)";
                using (SqlCommand cmd = new SqlCommand(query, sqlcon))
                {
                    cmd.Parameters.Add(new SqlParameter("Name", s.Name));
                    cmd.Parameters.Add(new SqlParameter("Id", s.Id));
                    cmd.Parameters.Add(new SqlParameter("Album", s.Album));
                    cmd.Parameters.Add(new SqlParameter("TrackNumber", s.TrackNumber));
                    cmd.Parameters.Add(new SqlParameter("TrackNumberCount", s.TrackNumberCount));
                    cmd.Parameters.Add(new SqlParameter("Genre",s.Genre));
                    cmd.Parameters.Add(new SqlParameter("Rating", s.Rating));
                    cmd.Parameters.Add(new SqlParameter("Tags", s.Tags));
                    cmd.Parameters.Add(new SqlParameter("Subject", s.Subject));
                    cmd.Parameters.Add(new SqlParameter("Categories", s.Categories));
                    cmd.Parameters.Add(new SqlParameter("Comments", s.Comments));
                    cmd.Parameters.Add(new SqlParameter("FileName", s.FileName));
                    cmd.Parameters.Add(new SqlParameter("FolderName", s.FolderName));
                    cmd.Parameters.Add(new SqlParameter("FolderPath", s.FolderPath));
                    cmd.Parameters.Add(new SqlParameter("FullPath", s.FullPath));
                    cmd.Parameters.Add(new SqlParameter("Length", s.Length));
                    cmd.Parameters.Add(new SqlParameter("PlayCount", s.PlayCount));
                    cmd.Parameters.Add(new SqlParameter("SkipCount", s.SkipCount));
                    cmd.Parameters.Add(new SqlParameter("LastPlayed", s.LastPlayed));
                    cmd.ExecuteNonQuery();
                    sqlcon.Close();
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Count not insert. {0}", s.Name);
                Console.WriteLine("Error Message {0}", ex.Message);
            }

        }
    }

如果有人能告诉我我需要做什么来简单地添加到现有的表中而不覆盖它，那么任何帮助都将非常有用。非常感谢。

如果你很好奇，这是我快速填充表格的方法：

 public static void JustDoIt()
    {
        Songs s = new Songs();
        for (int i = 1; i <= 500; i++)
        {
            s.Name = "My Song Name " + i.ToString("D3");
            s.Id = i.ToString();
            s.Album = "My Song's Album " + i.ToString("D3");
            s.TrackNumber = (i%13 == 0 ? 1: i%13).ToString("D3");
            s.TrackNumberCount = "12";
            s.Genre = "Something";
            s.Rating = (i%20/100*i).ToString("D3");
            s.Tags = "Tags " + i.ToString("D3") + " and more tags";
            s.Subject = "Subjects";
            s.Categories = "Categories";
            s.Comments = "Comments";
            s.FileName = "Ashes Remain - Christmas  - 02 - Gift of Love.mp3";
            s.FolderName = "My folder name";
            s.FolderPath = @"L:'Dropbox'Music'00- Sync'd Music'Ashes Remain";
            s.FullPath = s.FolderName + "''" + s.FolderPath;
            s.Length = "3:" + i/60;
            s.PlayCount = "12";
            s.SkipCount = "1";
            s.LastPlayed = DateTime.Now.ToString();
            SQL_AddNewRecord.AddSongViaClass(s);
            Console.WriteLine(i);
        }
    }

谢谢！

            using (SqlCommand cmd = new SqlCommand(query, sqlcon))
            {
                cmd.Parameters.Add(new SqlParameter("Name", s.Name));
                cmd.Parameters.Add(new SqlParameter("Id", s.Id));
                cmd.Parameters.Add(new SqlParameter("Album", s.Album));
                cmd.Parameters.Add(new SqlParameter("TrackNumber", s.TrackNumber));
                cmd.Parameters.Add(new SqlParameter("TrackNumberCount", s.TrackNumberCount));
                cmd.Parameters.Add(new SqlParameter("Genre", s.Genre));
                cmd.Parameters.Add(new SqlParameter("Rating", s.Rating));
                cmd.Parameters.Add(new SqlParameter("Tags", s.Tags));
                cmd.Parameters.Add(new SqlParameter("Subject", s.Subject));
                cmd.Parameters.Add(new SqlParameter("Categories", s.Categories));
                cmd.Parameters.Add(new SqlParameter("Comments", s.Comments));
                cmd.Parameters.Add(new SqlParameter("FileName", s.FileName));
                cmd.Parameters.Add(new SqlParameter("FolderName", s.FolderName));
                cmd.Parameters.Add(new SqlParameter("FolderPath", s.FolderPath));
                cmd.Parameters.Add(new SqlParameter("FullPath", s.FullPath));
                cmd.Parameters.Add(new SqlParameter("Length", s.Length));
                cmd.Parameters.Add(new SqlParameter("PlayCount", s.PlayCount));
                cmd.Parameters.Add(new SqlParameter("SkipCount", s.SkipCount));
                cmd.Parameters.Add(new SqlParameter("LastPlayed", s.LastPlayed));
                cmd.ExecuteNonQuery();
                for (int i = 1; i <= 500; i++)
                {
                    cmd.Parameters["Name"].Value = "My Song Name " + i.ToString("D3");
                    cmd.Parameters["Id"].Value = i.ToString();
                    ...All parameters...
                    cmd.ExecuteNonQuery();
                }
                sqlcon.Close();