Specified iterator not found error?

I have started receiving the following error when querying Datomic Cloud:
clojure.lang.ExceptionInfo: Datomic Client Exception {:cognitect.anomalies/category :cognitect.anomalies/busy, :datomic.client/http-result {:status nil, :headers nil, :body nil}}.

The error only occurs on some queries. It seems like the queries that would have a larger result set return this error while queries with smaller result sets return successfully.

What does this error mean?

From the anomalies docs (https://github.com/cognitect-labs/anomalies), busy is just that, and you should retry the operation. If that’s not working for you, per the client API docs, you can try increasing the timeout (https://docs.datomic.com/client-api/datomic.client.api.html)

Thanks. I copy and pasted the wrong error message. Datomic does, indeed, have a bug.
The conditions that trigger the bug aren’t entirely clear to me but involve a rather larger result set (> 500k datoms).

Datomic support has been great to work with and is working on a fix now.