Since I made this comment and submitted this PR, the Firebase SDK documentation appears to have been updated and equalTo and endAt are documented as supporting the optional key parameter:
This argument is only allowed if ordering by child, value, or priority.
AngularFire2 should also support the optional key parameter for equalTo and endAt.
There is a plunk here that demonstrates the SDK usage.
Since I made this comment and submitted this PR, the Firebase SDK documentation appears to have been updated and
equalToandendAtare documented as supporting the optionalkeyparameter:AngularFire2 should also support the optional
keyparameter forequalToandendAt.There is a plunk here that demonstrates the SDK usage.