How can I use GLOBAL IN in this module?

[wangchenghan]

I was using sqlachemy to do a Double-distributed IN/JOIN subqueries, whose sql looks like
SELECT * FROM table_a WHERE field_a global in ( SELECT filed_a FROM table b )
The sql works well. But in order to keep the code clean, I need write it in ORM way, like
query(cls.field_a.in(table_b.subquery())
I can't find where to put the keyword global in. So I just got the exception
Double-distributed IN/JOIN subqueries is denied (distributed_product_mode = 'deny').
Is there any one knows how to solve this?