From 0a56966f7d4879f9d517c96a3c714accdce4e17f Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Mon, 3 Jun 2019 17:42:52 +0100
Subject: [PATCH] Fix

---
 synapse/storage/stats.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/synapse/storage/stats.py b/synapse/storage/stats.py
index 1f39ef211a..ff266b09b0 100644
--- a/synapse/storage/stats.py
+++ b/synapse/storage/stats.py
@@ -340,7 +340,8 @@ class StatsStore(StateDeltasStore):
             "avatar",
             "canonical_alias"
         ):
-            if "\0" in fields.get(col, ""):
+            field = fields.get(col)
+            if field and "\0" in field:
                 fields[col] = None
 
         return self._simple_upsert(