Hi Tim,
I looked into it and I believe it is not possible for the following reason:
At the time when the where clause is composed for the second query, the result from the first one is not available. The where clause cannot include a reference to a result, it should be a complete scalar value by the time the entire sequence of operations is sent to the server in the transaction. Here’s a visual representation of what I mean:
I apologize for not catching it earlier at the beginning of this thread.
The following graphic from our docs actually shows that none of the errors come into the “Retrieving Objects” block, this means the data retrieval operation cannot use a result of another operation:
Regards,
Mark