From d16f1df8cd9c1ae2635979e158340b2bd19fb178 Mon Sep 17 00:00:00 2001
From: Stefan Wehrmeyer <mail@stefanwehrmeyer.com>
Date: Sun, 20 Dec 2015 13:15:39 +0100
Subject: [PATCH] Don't call fetch on closed result proxy

"The DBAPI cursor will be closed by the ResultProxy when all of its result rows (if any) are exhausted"
See http://docs.sqlalchemy.org/en/latest/core/connections.html
---
 dataset/persistence/util.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/dataset/persistence/util.py b/dataset/persistence/util.py
index c1a89c0..b67a348 100644
--- a/dataset/persistence/util.py
+++ b/dataset/persistence/util.py
@@ -50,6 +50,8 @@ class ResultIter(object):
         self._iter = None
 
     def _next_chunk(self):
+        if self.result_proxy.closed:
+            return False
         if not self.step:
             chunk = self.result_proxy.fetchall()
         else: