2026-04-29-21-51-19 - 全栈系统改造：FastAPI后端+SAM2+PostgreSQL+Redis+MinIO+前端Zustand重构

backend/database.py

@@ -0,0 +1,29 @@
+"""Database configuration using synchronous SQLAlchemy."""
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import declarative_base, sessionmaker, Session
+from fastapi import Depends
+from typing import Generator
+
+from config import settings
+
+engine = create_engine(
+    settings.db_url,
+    pool_pre_ping=True,
+    pool_size=10,
+    max_overflow=20,
+    echo=False,
+)
+
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+Base = declarative_base()
+
+
+def get_db() -> Generator[Session, None, None]:
+    """FastAPI dependency that yields a database session."""
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()