Can I inspect a sqlalchemy query object to find the already joined tables?

Question

I\'m trying to programmatically build a search query, and to do so, I\'m joining a table.

class User(db.Model):
    id = db.Column(db.Integer(), primary_key=         


        

Answer 1

According to the r-m-n answer:

Some where in your initialization of your project, add a unique_join method to the sqlalchemy.orm.Query object like this:

def unique_join(self, *props, **kwargs):
    if props[0] in [c.entity for c in self._join_entities]:
        return self
    return self.join(*props, **kwargs)

Query.unique_join = unique_join

Now use query.unique_join instead of query.join:

query = query.unique_join(Tag)

Answer 2

You can find joined tables in query._join_entities

joined_tables = [mapper.class_ for mapper in query._join_entities]