The SELECT query that you posted won't work. Please post the query that you actually used.
The problem that I think you are having is that you've specified both columns in your GROUP BY clause. This implies that each group will have only one member row unless there are two rows that have exactly the same ID and field1 values (both rows have identical values in all columns).
If you can post the query that you actually used, I'm sure that someone can help you with it.