backend/database.py

from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker, DeclarativeBase
from config import DATABASE_URL

connect_args = {"check_same_thread": False} if DATABASE_URL.startswith("sqlite") else {}

engine = create_engine(DATABASE_URL, connect_args=connect_args)
SessionLocal = sessionmaker(bind=engine, autoflush=False, autocommit=False)

class Base(DeclarativeBase):
    pass

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