public List<string> GetLanes ()
{
List<string> result = new List<string> ();
using (IDbCommand cmd = CreateCommand ()) {
cmd.CommandText = "SELECT DISTINCT lane FROM Revision";
using (IDataReader reader = cmd.ExecuteReader ()) {
while (reader.Read ())
result.Add (reader.GetString (0));
}
}
return result;
}