A digest of all the documents that match a given target.
.. attribute:: target_id
The target ID to which this filter applies.
:type: int
Attribute
Name
Description
count
int
The total count of documents that match
target_id][google.firestore.v1.ExistenceFilter.target_id].
If different from the count of documents in the client that
match, the client must manually determine which documents no
longer match the target.