C# と VB.NET の質問掲示板

■No89486 (あかかきき さん) に返信
> 末尾にF列、G列を追加し、それぞれ、C列とE列の値の半分をいれたい


if (IntPtr.Size == 4)
{
    string folder = @"C:\TEST\";
    string srcFile = @"EXAMPLE.CSV";
    string dstFile = @"RESULT.CSV";

    string cs1 = @"Driver={Microsoft Text Driver (*.txt; *.csv)};DBQ=" + folder;

    string cs2 = $@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={folder};"
                + @"Extended Properties=""Text;IMEX=1;HDR=YES;FMT=Delmited"";";

    using (var con = new OdbcConnection(cs1))
  //using (var con = new OleDbConnection(cs2))
    using (var cmd = con.CreateCommand())
    {
        cmd.CommandText =
             $@"SELECT A,B,C,D,E, (C/2) AS [F], (E/2) AS [G]
             INTO `{dstFile}`
             FROM `{srcFile}` ";

        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
    }
}