From e0e43deaec26384766a61874db4aaa6bda4ae415 Mon Sep 17 00:00:00 2001
From: Hagen Rother <hagen.rother@liquidm.com>
Date: Fri, 4 Apr 2014 13:04:40 +0200
Subject: [PATCH] fix a NPE leading to broker 500 response

---
 .../main/java/io/druid/query/groupby/GroupByQueryEngine.java    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/processing/src/main/java/io/druid/query/groupby/GroupByQueryEngine.java b/processing/src/main/java/io/druid/query/groupby/GroupByQueryEngine.java
index ea58501635b..b8f63a5c4a5 100644
--- a/processing/src/main/java/io/druid/query/groupby/GroupByQueryEngine.java
+++ b/processing/src/main/java/io/druid/query/groupby/GroupByQueryEngine.java
@@ -182,7 +182,7 @@ public class GroupByQueryEngine
 
         final DimensionSelector dimSelector = dims.get(0);
         final IndexedInts row = dimSelector.getRow();
-        if (row.size() == 0) {
+        if (row == null || row.size() == 0) {
           ByteBuffer newKey = key.duplicate();
           newKey.putInt(dimSelector.getValueCardinality());
           unaggregatedBuffers = updateValues(newKey, dims.subList(1, dims.size()));