diff --git a/apps/api/src/db/base.py b/apps/api/src/db/base.py
index f7e16f11..e17a68ab 100644
--- a/apps/api/src/db/base.py
+++ b/apps/api/src/db/base.py
@@ -144,7 +144,9 @@ async def init_db() -> None:
     """
     engine = get_engine()
     async with engine.begin() as conn:
-        await conn.run_sync(Base.metadata.create_all)
+        # checkfirst=True: 存在的 table/index 直接跳過，避免 rolling update 重啟時
+        # "relation already exists" CrashLoopBackOff（2026-04-15 Claude Sonnet 4.6 Phase 3 修復）
+        await conn.run_sync(lambda c: Base.metadata.create_all(c, checkfirst=True))
 
         # 2026-04-02 Claude Code: 確保 risklevel enum 包含 'high' 值
         # Phase 23 新增，避免舊 DB 缺少此值導致 InvalidTextRepresentation