Compare two csv files with same columns

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C#

MySQL

CSV

MySQL-Connector

I need to import two csv files to mysql database table, but when I will import the second file I want to compare it to the first file inserted in the database, and if there is a difference in a row I will insert the row of the second file.

I have tried to import directly the second file, but the result in the database still with data of the first file also not organized.

First, I uploaded and save the first file, then when I uploaded the second file I didn't see in the database table the data correctly of the second file I want a method to update if there is a difference or add new rows if exist in the second file

Here's my method to import and save the first csv file

What I have tried:

private void Import_Bilan_Click(object sender, EventArgs e)
        {
            DialogResult result = openFileDialog1.ShowDialog(); // Show the dialog.
            if (result == DialogResult.OK) // Test result.
            {
                string file = openFileDialog1.FileName;
                string[] f = file.Split('\\');

                // to get the only file name
                string fn = f[(f.Length) - 1];
                string path = Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
                string dest = path + @"\upload\" + fn;

                //to copy the file to the destination folder
                File.Copy(file, dest, true);
                MessageBox.Show("File Uploaded !!");

                //to copy the file to the destination folder
                File.Copy(file, dest, true);

                MySqlConnection con = new MySqlConnection("datasource=localhost;database=altares;port=3306;username=root;password=root;SslMode=none;AllowUserVariables=true");
                var msbl = new MySqlBulkLoader(con)
                {
                    TableName = "exercices",
                    FieldTerminator = ";",
                    FileName = dest,
                    NumberOfLinesToSkip = 1,

                };
                msbl.Columns.AddRange(new[] { "siren", "designation", "annee", "@discard", "@discard", "@discard", "@discard", "@discard", "AA", "AB", "AC", "AD", "AE", "AF", "AG", "AH", "AI", "AJ", "Ak", "AL", "AM", "AN", "AO", "AP", "AQ", "AR","@discard", "AT", "AU", "AV", "AW", "AX", "AY", "CS", "CT", "CU", "CV", "BB", "BC", "BD", "BE", "BF", "BG", "BH", "BI", "BJ", "BK", "BL", "BM", "BN", "BO", "BP", "BQ", "BR", "BS","YP" });

                msbl.Load();
                con.Close();

                MessageBox.Show("Bilan bind to database !!");
            }
        }