diff --git a/index-common/src/main/java/com/metamx/druid/index/serde/BitmapIndexColumnPartSupplier.java b/index-common/src/main/java/com/metamx/druid/index/serde/BitmapIndexColumnPartSupplier.java
index b282ab56a5c..6813541ef09 100644
--- a/index-common/src/main/java/com/metamx/druid/index/serde/BitmapIndexColumnPartSupplier.java
+++ b/index-common/src/main/java/com/metamx/druid/index/serde/BitmapIndexColumnPartSupplier.java
@@ -51,7 +51,12 @@ public class BitmapIndexColumnPartSupplier implements Supplier<BitmapIndex>
       {
         final int index = dictionary.indexOf(value);
 
-        return index >= 0 ? bitmaps.get(index) : EMPTY_SET;
+        if (index < 0) {
+          return EMPTY_SET;
+        }
+
+        final ImmutableConciseSet bitmap = bitmaps.get(index);
+        return bitmap == null ? EMPTY_SET : bitmap;
       }
     };
   }
diff --git a/index-common/src/main/java/com/metamx/druid/index/serde/ComplexColumnPartSerde.java b/index-common/src/main/java/com/metamx/druid/index/serde/ComplexColumnPartSerde.java
index 7e425f9f525..760fcbb3f20 100644
--- a/index-common/src/main/java/com/metamx/druid/index/serde/ComplexColumnPartSerde.java
+++ b/index-common/src/main/java/com/metamx/druid/index/serde/ComplexColumnPartSerde.java
@@ -36,25 +36,28 @@ public class ComplexColumnPartSerde implements ColumnPartSerde
 {
   @JsonCreator
   public static ComplexColumnPartSerde createDeserializer(
-      @JsonProperty("complexType") String complexType
+      @JsonProperty("typeName") String complexType
   )
   {
     return new ComplexColumnPartSerde(null, complexType);
   }
 
   private final GenericIndexed column;
+  private final String typeName;
+
   private final ComplexMetricSerde serde;
 
-  public ComplexColumnPartSerde(GenericIndexed column, String complexType)
+  public ComplexColumnPartSerde(GenericIndexed column, String typeName)
   {
     this.column = column;
-    serde = ComplexMetrics.getSerdeForType(complexType);
+    this.typeName = typeName;
+    serde = ComplexMetrics.getSerdeForType(typeName);
   }
 
   @JsonProperty
-  public GenericIndexed getColumn()
+  public String getTypeName()
   {
-    return column;
+    return typeName;
   }
 
   @Override
diff --git a/server/src/main/java/com/metamx/druid/index/v1/IndexMerger.java b/server/src/main/java/com/metamx/druid/index/v1/IndexMerger.java
index 4eb8db5fcc7..57828855b38 100644
--- a/server/src/main/java/com/metamx/druid/index/v1/IndexMerger.java
+++ b/server/src/main/java/com/metamx/druid/index/v1/IndexMerger.java
@@ -79,6 +79,7 @@ import java.util.Iterator;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.TreeSet;
 
 /**
@@ -784,13 +785,11 @@ public class IndexMerger
 
   private static <T extends Comparable> ArrayList<T> mergeIndexed(final List<Iterable<T>> indexedLists)
   {
-    LinkedHashSet<T> retVal = Sets.newLinkedHashSet();
+    Set<T> retVal = Sets.newTreeSet(Ordering.<T>natural().nullsFirst());
 
     for (Iterable<T> indexedList : indexedLists) {
       for (T val : indexedList) {
-        if (val != null) {
-          retVal.add(val);
-        }
+        retVal.add(val);
       }
     }
 
diff --git a/server/src/main/java/com/metamx/druid/index/v1/QueryableIndexIndexableAdapter.java b/server/src/main/java/com/metamx/druid/index/v1/QueryableIndexIndexableAdapter.java
index 72eddb9141c..d05864716af 100644
--- a/server/src/main/java/com/metamx/druid/index/v1/QueryableIndexIndexableAdapter.java
+++ b/server/src/main/java/com/metamx/druid/index/v1/QueryableIndexIndexableAdapter.java
@@ -19,12 +19,14 @@
 
 package com.metamx.druid.index.v1;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 import com.google.common.io.Closeables;
 import com.metamx.common.ISE;
 import com.metamx.druid.index.QueryableIndex;
+import com.metamx.druid.index.column.BitmapIndex;
 import com.metamx.druid.index.column.Column;
 import com.metamx.druid.index.column.ComplexColumn;
 import com.metamx.druid.index.column.DictionaryEncodedColumn;
@@ -32,6 +34,7 @@ import com.metamx.druid.index.column.GenericColumn;
 import com.metamx.druid.index.column.ValueType;
 import com.metamx.druid.kv.ArrayBasedIndexedInts;
 import com.metamx.druid.kv.ConciseCompressedIndexedInts;
+import com.metamx.druid.kv.EmptyIndexedInts;
 import com.metamx.druid.kv.Indexed;
 import com.metamx.druid.kv.IndexedInts;
 import com.metamx.druid.kv.IndexedIterable;
@@ -91,7 +94,18 @@ public class QueryableIndexIndexableAdapter implements IndexableAdapter
   @Override
   public Indexed<String> getDimValueLookup(String dimension)
   {
-    final DictionaryEncodedColumn dict = input.getColumn(dimension).getDictionaryEncoding();
+    final Column column = input.getColumn(dimension);
+
+    if (column == null) {
+      return null;
+    }
+
+    final DictionaryEncodedColumn dict = column.getDictionaryEncoding();
+
+    if (dict == null) {
+      return null;
+    }
+
     return new Indexed<String>()
     {
       @Override
@@ -244,9 +258,18 @@ public class QueryableIndexIndexableAdapter implements IndexableAdapter
   @Override
   public IndexedInts getInverteds(String dimension, String value)
   {
-    return new ConciseCompressedIndexedInts(
-        input.getColumn(dimension).getBitmapIndex().getConciseSet(value)
-    );
+    final Column column = input.getColumn(dimension);
+
+    if (column == null) {
+      return new EmptyIndexedInts();
+    }
+
+    final BitmapIndex bitmaps = column.getBitmapIndex();
+    if (bitmaps == null) {
+      return new EmptyIndexedInts();
+    }
+
+    return new ConciseCompressedIndexedInts(bitmaps.getConciseSet(value));
   }
 
   @Override