app/services/db.py

from sqlalchemy import create_engine, Column, String, DateTime
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from datetime import datetime

# Using in-memory SQLite for demo
SQLALCHEMY_DATABASE_URL = "sqlite:///:memory:"

engine = create_engine(
    SQLALCHEMY_DATABASE_URL, 
    connect_args={"check_same_thread": False},
    echo=False  # Disable logging for performance
)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

Base = declarative_base()

class User(Base):
    __tablename__ = "users"
    id = Column(String, primary_key=True)
    email = Column(String, unique=True, index=True)
    password_hash = Column(String)
    created_at = Column(DateTime, default=datetime.utcnow)