How to group documents by field1 and then query to see field2 is missing a value?

[steevej (Steeve Juneau)]

Sample documents for all you use-cases including:

@Ram_Mulay

there are other documents with the same transaction_id which have statuses that are not “delivered”, “undelivered”, “failed”. Hence the query returns both transaction_ids - “1” and “2”.

Read Formatting code and log snippets in posts before supplying all documents we need to experiment.

Share exactly the code you

@Ram_Mulay

have tried - $ne or $nin

My approach would be to group on transaction_id using $addToSet for the status. Then a $match a $nin on the $addToSet array.