Data inconsistency issue when using SQLAlchemy with PostgreSQL in Python 3.10
I'm working on a personal project and I'm encountering a data inconsistency issue while using SQLAlchemy with PostgreSQL in my Python 3.10 application. I have a simple model that consists of two related tables: `User` and `Profile`. After running a bulk insert operation using `session.bulk_insert_mappings()`, I noticed that some `Profile` entries are missing their corresponding `User` IDs, leading to integrity errors when I try to access the `Profile` objects. Here's the relevant part of my code: ```python from sqlalchemy import create_engine, Column, Integer, String, ForeignKey from sqlalchemy.orm import sessionmaker, relationship, declared_attr from sqlalchemy.ext.declarative import declarative_base Base = declarative_base() class User(Base): __tablename__ = 'users' id = Column(Integer, primary_key=True) name = Column(String) profile = relationship('Profile', back_populates='user') class Profile(Base): __tablename__ = 'profiles' id = Column(Integer, primary_key=True) user_id = Column(Integer, ForeignKey('users.id')) bio = Column(String) user = relationship('User', back_populates='profile') engine = create_engine('postgresql://user:password@localhost/mydatabase') Session = sessionmaker(bind=engine) session = Session() # Bulk insert users users_data = [{'name': 'Alice'}, {'name': 'Bob'}] session.bulk_insert_mappings(User, users_data) # Attempting to insert profiles profiles_data = [{'bio': 'Hello, I am Alice!'}, {'bio': 'Hello, I am Bob!'}] try: session.bulk_insert_mappings(Profile, profiles_data) session.commit() except Exception as e: session.rollback() print(f'Error: {e}') ``` I expected the `user_id` in the `Profile` table to automatically match the IDs of the newly created users, but it seems that the `session` is not aware of the primary keys assigned during the bulk insert. I've checked the SQLAlchemy documentation and tried using `session.flush()` before the bulk insert for `Profile`, but that didn't resolve the issue. Any insights on how to properly associate the profiles with their corresponding users while ensuring data integrity would be greatly appreciated. Any help would be greatly appreciated!