How to use NOT IN clause in sqlalchemy ORM query

Question

how do i convert the following mysql query to sqlalchemy?

SELECT * FROM `table_a` ta, `table_b` tb where 1 AND ta.id = tb.id AND ta.id not in (select id from `table_c`) 

so far i have this for sqlalchemy:

query = session.query(table_a, table_b) query = query.filter(table_a.id == table_b.id) 

Answer 1

The ORM internals describe the not_in() operator (previously notin_()), so you can say:

query = query.filter(table_a.id.not_in(subquery)) #                               ^^^^^^ 

From the docs:

inherited from the ColumnOperators.not_in() method of ColumnOperators

implement the NOT IN operator.

This is equivalent to using negation with ColumnOperators.in_(), i.e. ~x.in_(y).

Note that version 1.4 states:

The not_in() operator is renamed from notin_() in previous releases. The previous name remains available for backwards compatibility.

So you may find notin_() in some cases.

Answer 2

Try this:

subquery = session.query(table_c.id) query = query.filter(~table_a.id.in_(subquery)) 

Note: table_a, table_b and table_c should be mapped classes, not Table instances.