Speed issues retrieving large hierarchy

this is client or server-side error?

this error means that something initializes streamer twice.
what code causes it?

I think I might have found it - I’ve got a lookup in one of the tables and the lookup datatable isn’t open. When it tries to open it whilst processing the Fill, it throws the above exception.

try to specify lookup table as first table in RDA.Fill

It’s ok, the lookups should be open before the Fill but I was neglecting to open one of them