Data Model in Service duplicating and replacing rows

Hi Ed. As I said over email, we've identified the root cause of this issue. We're currently targeting the fix for our July release.

In the meantime, you can work around the issue by ensuring that your folded queries are always sorted. This can be done by always including (and preserving in downstream queries) all primary keys for a given table. Or, if this isn't possible (as in your case when doing a Group By operation), you can explicitly sort by a set of unique keys before combining. (Also note that it may be necessary to buffer after sorting and before combining to ensure the sort is applied by the folding layer. You'll have to experiment to see whether or not this is necessary.)

Ehren