app/database.py

from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from app.config import settings

# For SQLite, check_same_thread must be False for multithreading (FastAPI async requests)
connect_args = {}
if settings.DATABASE_URL.startswith("sqlite"):
    connect_args = {"check_same_thread": False}

engine = create_engine(
    settings.DATABASE_URL,
    connect_args=connect_args,
    echo=False
)

SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

Base = declarative_base()

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