When should I use a CompiledQuery?

Question

I have a table:

-- Tag

ID  | Name
-----------
1   | c#
2   | linq
3   | entity-framework

I have a class that will have the following methods:

IEnumerable<Tag> GetAll();
IEnumerable<Tag> GetByName();

Should I use a compiled query in this case?

static readonly Func<Entities, IEnumerable<Tag>> AllTags =
    CompiledQuery.Compile<Entities, IEnumerable<Tag>>
    (
        e => e.Tags
    );

Then my GetByName method would be:

IEnumerable<Tag> GetByName(string name)
{
    using (var db = new Entities())
    {
        return AllTags(db).Where(t => t.Name.Contains(name)).ToList();
    }
}

Which generates a SELECT ID, Name FROM Tag and execute Where on the code. Or should I avoid CompiledQuery in this case?

Basically I want to know when I should use compiled queries. Also, on a website they are compiled only once for the entire application?