Better way to consume an IEnumerable<IEnumerable<string>>

Question

I'm calling a stored procedure with multiple results sets (always 2) and writing the results to seperate files (in pipe delimited format). I can't split the results sets into seperate stored procs. I'm using IDataReader and IEnumerable to keep as little in memory in the process.

Is there a cleaner way of consuming my IEnumerable<IEnumerable<string>> than using GetEnumerator/MoveNext/Current to get to the inner IEnumerable<string> to pass to File.AppendAllLines?

    public void Execute()
    {
        var reader = GetLines();

        using (var enumerator = reader.GetEnumerator())
        {
            enumerator.MoveNext();

            File.AppendAllLines("file1.dat", enumerator.Current);
            enumerator.MoveNext();

            File.AppendAllLines("file2.dat", enumerator.Current);
        }
    }

    public IEnumerable<IEnumerable<string>> GetLines()
    {
        Database db = DatabaseFactory.CreateDatabase("connectionStringKey");
        using (var command = db.GetStoredProcCommand("getdata_sp"))
        {
            var reader = db.ExecuteReader(command);
            yield return GetInnerEnumerable(reader);
            reader.NextResult();
            yield return GetInnerEnumerable(reader);
        }
    }

    private IEnumerable<string> GetInnerEnumerable(IDataReader reader)
    {
        while (reader.Read())
        {
            object[] rowValues = new object[reader.FieldCount];
            reader.GetValues(rowValues);
            yield return String.Join("|", rowValues);
        }
    }

Answer 1

Why not a foreach loop? That is the most basic.

Answer 2

Personally, I would just use a foreach loop with a separate variable for tracking which file to write to, something like:

public void Execute()
{
    var reader = GetLines();

    int i = 0;
    foreach (var inner in reader)
    {
        if (i % 2 == 0)
            File.AppendAllLines("file1.dat", inner);
        else
            File.AppendAllLines("file2.dat", inner);
        ++i;
    }
}