q = session.query(Table1.field1, Table1.field2)\
.outerjoin(Table2)\ # use in case you have relationship defined
# .outerjoin(Table2, Table1.id == Table2.table_id)\ # use if you do not have relationship defined
.filter(Table2.tbl2_id == None)
should do it, assuming that field1
and field2
are from Table1
, and that you define a relationship:
class Table2(Base):
# ...
table1 = relationship(Table1, backref="table2s")