Microsoft.Mashup.Evaluator.Interface.ErrorException: Attempted to read or write protected memory.

Thank you for the reply. 

It turns out that the issue was the code. The code I was passing through DirectQuery to the Oracle backend was in ANSI-89 format, similar to the below:

select a.id, b.id, b.address_1
from person a, address b
where a.id = b.id

Once the code was converted to ANSI-92 format, the error message went away. 

select a.id, b.id, b.address_1
from person a
inner join address b
on a.id = b.id

Is this documented somewhere? If not, this should be. 

-Igor