Question

I have to load and use my data from a db. The data is represented like this:

group_id    term
1           hello
1           world
1           bye
2           foo
2           bar

etc.

What is a good C# collection to load and use this data?

Answer 1

Looks like you need a Dictionary<int, List<string>>:

var dict = new Dictionary<int, List<string>>();

var dict.Add(1, new List<string> { "hello", "world", "bye" });
var dict.Add(2, new List<string> { "foo", "bar" });