Error with sessionmaker

Question

I can see from this question Why are session methods unbound in sqlalchemy using sqlite? that I need to instantiate the class for sessionmaker.

I get the same error, and I assume the 'fix' will work, only I have no idea how to 'instantiate the class'

My set up code is as per the linked question.

From this question How to instantiate a class in python I can see that I need to call the class object, and my erroneous assumption is that the:

session = sessionmaker(bind=engine)

line is the instantiation.

score 32 · Accepted Answer · answered Apr 22 '12 at 01:03

32

Your problem is exactly the same as the first question you posted, and the solution should be the same as the selected answer from the same question.

The function sessionmaker returns a class, binding the engine passed in the bind parameter.

So, after creating the class, you have to instantiate it (haven't instantiate it yet):

Session = sessionmaker(bind=engine)
# Session is a class
session = Session()
# now session is a instance of the class Session
session.execute(...)

answered Apr 22 '12 at 01:03

juliomalegria

Awesome, I was aware they are the same, I just didn't know how to the middle step of actually calling it as an object rather than as a class. Thank you for setting me straight. – Jay Gattuso Apr 22 '12 at 02:18

score 7 · Answer 2 · answered Apr 22 '12 at 01:01

7

That line creates the Session class. You still need to instantiate it.

Session = sessionmaker(bind=engine)
session = Session()

answered Apr 22 '12 at 01:01

2 Answers2