Feat: [main] baekjoon-bot-v1

db.py

@@ -0,0 +1,21 @@
+import os
+from typing import AsyncGenerator
+
+from sqlalchemy.ext.asyncio import create_async_engine, async_sessionmaker, AsyncSession
+
+DATABASE_URL = os.getenv("DATABASE_URL", "").strip()
+if not DATABASE_URL:
+    raise RuntimeError("DATABASE_URL is required (e.g. postgresql+asyncpg://...)")
+
+engine = create_async_engine(DATABASE_URL, pool_pre_ping=True)
+
+SessionLocal = async_sessionmaker(
+    bind=engine,
+    class_=AsyncSession,
+    autoflush=False,
+    expire_on_commit=False,
+)
+
+async def get_db() -> AsyncGenerator[AsyncSession, None]:
+    async with SessionLocal() as session:
+        yield session