SQLite

:)

Use LINQ to CSV.

http://www.codeproject.com/KB/linq/LINQtoCSV.aspx

http://www.thinqlinq.com/Post.aspx/Title/LINQ-to-CSV-using-DynamicObject.aspx

If its not CSV in that case

Let your file hold one record per line. Each record at runtime should be read into a Collection of type Record [assuming Record is custom class representing individual record]. You can do LINQ operations on the collection and write back the collection into file.

Use ODBC. There is a Microsoft Text Driver for csv-Files. I think this would be possible. I don t have tested if you can manipulate via ODBC, but you can test it easily. For querying you can also use linq.

Have you looked at the FileHelpers library? It has the capability of reading and parsing a text file into CLR objects. Combining that with the power of something like LINQ to Objects, you have the functionality you need.

public class Item
{
    public int ID { get; set; }
    public string Type { get; set; }
    public string Instance { get; set; }
}

class Program
{
    static void Main(string[] args)
    {
        string[] lines = File.ReadAllLines("database.txt");

        var list = lines
                .Select(l =>
                    {
                        var split = l.Split( , );
                        return new Item
                        {
                            ID = int.Parse(split[0]),
                            Type = split[1],
                            Instance = split[2]
                        };
                    });

        Item secondItem = list.Where(item => item.ID == 2).Single();

        List<Item> newList = list.ToList<Item>();
        newList.RemoveAll(item => item.ID == 2);

        //override database.txt with new data from "newList"
    }
}

What about data delete. LINQ for query, not for manipulation. However, List provides a predicate-based RemoveAll that does what you want:

newList.RemoveAll(item => item.ID == 2);

Also you can overview more advanced solution "LINQ to Text or CSV Files"

I would also suggest to use ODBC. This should not complicate the deployment, the whole configuration can be set in the connection-string so you do not need a DSN.

Together with a schema.ini file you can even set column names and data-types, check this KB article from MS.

sqllite or linq to text and csv :)