backend/app/database/db.py

from sqlalchemy import create_engine
from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker

from app.config import settings

engine = create_engine(
    settings.database_url, connect_args={"check_same_thread": False}
)
SessionLocal = sessionmaker(bind=engine, autoflush=False, expire_on_commit=False)


class Base(DeclarativeBase):
    pass


def init_db():
    from app.database import models  # noqa: F401 — register tables

    Base.metadata.create_all(bind=engine)


def get_db():
    db: Session = SessionLocal()
    try:
        yield db
    finally:
        db.close()