diff --git a/src/main/java/com/loafle/overflow/crawler/result/OFResultSetRow.java b/src/main/java/com/loafle/overflow/crawler/result/OFResultSetRow.java
index b5371e2..7df3e1a 100644
--- a/src/main/java/com/loafle/overflow/crawler/result/OFResultSetRow.java
+++ b/src/main/java/com/loafle/overflow/crawler/result/OFResultSetRow.java
@@ -58,6 +58,7 @@ public class OFResultSetRow extends OFResultSet{
 
         for (List<String> row : this.rows) {
             String key = makeKey(row);
+            if(key == null) continue;
             returnMap.put(key,row.get(this.meta.get(valueColumn)));
         }
 
@@ -86,6 +87,10 @@ public class OFResultSetRow extends OFResultSet{
             if (find == true) {break;}
         }
 
+        if(findIndex < 0) {
+            return null;
+        }
+
         String metric = metrics.get(findIndex).getMetric();
 
         if (arrayColumns != null) {