From de4553013a9a54e7b93d776c336222a622254fab Mon Sep 17 00:00:00 2001
From: Alexander Beedie <alexander-beedie@users.noreply.github.com>
Date: Tue, 18 Jun 2024 00:06:31 +0400
Subject: [PATCH] fix: Harden "async" check for users with out-of-date
 `sqlalchemy` libraries (#17029)

---
 py-polars/polars/io/database/_executor.py | 25 +++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/py-polars/polars/io/database/_executor.py b/py-polars/polars/io/database/_executor.py
index 49ddc6b6dc7c..d7b2d963dd06 100644
--- a/py-polars/polars/io/database/_executor.py
+++ b/py-polars/polars/io/database/_executor.py
@@ -318,21 +318,30 @@ def _inject_type_overrides(
     @staticmethod
     def _is_alchemy_async(conn: Any) -> bool:
         """Check if the cursor/connection/session object is async."""
-        from sqlalchemy.ext.asyncio import (
-            AsyncConnection,
-            AsyncSession,
-            async_sessionmaker,
-        )
+        try:
+            from sqlalchemy.ext.asyncio import (
+                AsyncConnection,
+                AsyncSession,
+                async_sessionmaker,
+            )
 
-        return isinstance(conn, (AsyncConnection, AsyncSession, async_sessionmaker))
+            return isinstance(conn, (AsyncConnection, AsyncSession, async_sessionmaker))
+        except ImportError:
+            return False
 
     @staticmethod
     def _is_alchemy_engine(conn: Any) -> bool:
         """Check if the cursor/connection/session object is async."""
         from sqlalchemy.engine import Engine
-        from sqlalchemy.ext.asyncio import AsyncEngine
 
-        return isinstance(conn, (Engine, AsyncEngine))
+        if isinstance(conn, Engine):
+            return True
+        try:
+            from sqlalchemy.ext.asyncio import AsyncEngine
+
+            return isinstance(conn, AsyncEngine)
+        except ImportError:
+            return False
 
     @staticmethod
     def _is_alchemy_session(conn: Any) -> bool: