diff --git a/processing/src/main/java/io/druid/query/filter/AndDimFilter.java b/processing/src/main/java/io/druid/query/filter/AndDimFilter.java
index 0364fa2e412..645db17ab3d 100644
--- a/processing/src/main/java/io/druid/query/filter/AndDimFilter.java
+++ b/processing/src/main/java/io/druid/query/filter/AndDimFilter.java
@@ -21,13 +21,10 @@ package io.druid.query.filter;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonProperty;
-import com.google.common.base.Function;
 import com.google.common.base.Joiner;
 import com.google.common.base.Preconditions;
-import com.google.common.collect.Lists;
 import io.druid.query.Druids;
 
-import java.util.Collections;
 import java.util.List;
 
 /**
@@ -43,7 +40,7 @@ public class AndDimFilter implements DimFilter
       @JsonProperty("fields") List<DimFilter> fields
   )
   {
-    fields.removeAll(Collections.singletonList(null));
+    fields = DimFilters.filterNulls(fields);
     Preconditions.checkArgument(fields.size() > 0, "AND operator requires at least one field");
     this.fields = fields;
   }
@@ -63,14 +60,8 @@ public class AndDimFilter implements DimFilter
   @Override
   public DimFilter optimize()
   {
-    return Druids.newAndDimFilterBuilder().fields(Lists.transform(this.getFields(), new Function<DimFilter, DimFilter>()
-    {
-      @Override
-      public DimFilter apply(DimFilter input)
-      {
-        return input.optimize();
-      }
-    })).build();
+    List<DimFilter> elements = DimFilters.optimize(fields);
+    return elements.size() == 1 ? elements.get(0) : Druids.newAndDimFilterBuilder().fields(elements).build();
   }
 
   @Override
diff --git a/processing/src/main/java/io/druid/query/filter/DimFilters.java b/processing/src/main/java/io/druid/query/filter/DimFilters.java
index fe8808a8601..8c084fbb09c 100644
--- a/processing/src/main/java/io/druid/query/filter/DimFilters.java
+++ b/processing/src/main/java/io/druid/query/filter/DimFilters.java
@@ -20,6 +20,9 @@
 package io.druid.query.filter;
 
 import com.google.common.base.Function;
+import com.google.common.base.Predicates;
+import com.google.common.collect.Collections2;
+import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
 
 import java.util.Arrays;
@@ -80,4 +83,25 @@ public class DimFilters
         )
     );
   }
+
+  public static List<DimFilter> optimize(List<DimFilter> filters)
+  {
+    return filterNulls(
+        Lists.transform(
+            filters, new Function<DimFilter, DimFilter>()
+            {
+              @Override
+              public DimFilter apply(DimFilter input)
+              {
+                return input.optimize();
+              }
+            }
+        )
+    );
+  }
+
+  public static List<DimFilter> filterNulls(List<DimFilter> optimized)
+  {
+    return Lists.newArrayList(Iterables.filter(optimized, Predicates.notNull()));
+  }
 }
diff --git a/processing/src/main/java/io/druid/query/filter/OrDimFilter.java b/processing/src/main/java/io/druid/query/filter/OrDimFilter.java
index 5016e6e41ad..52cbdb89210 100644
--- a/processing/src/main/java/io/druid/query/filter/OrDimFilter.java
+++ b/processing/src/main/java/io/druid/query/filter/OrDimFilter.java
@@ -21,13 +21,10 @@ package io.druid.query.filter;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonProperty;
-import com.google.common.base.Function;
 import com.google.common.base.Joiner;
 import com.google.common.base.Preconditions;
-import com.google.common.collect.Lists;
 import io.druid.query.Druids;
 
-import java.util.Collections;
 import java.util.List;
 
 /**
@@ -43,7 +40,7 @@ public class OrDimFilter implements DimFilter
       @JsonProperty("fields") List<DimFilter> fields
   )
   {
-    fields.removeAll(Collections.singletonList(null));
+    fields = DimFilters.filterNulls(fields);
     Preconditions.checkArgument(fields.size() > 0, "OR operator requires at least one field");
     this.fields = fields;
   }
@@ -63,14 +60,8 @@ public class OrDimFilter implements DimFilter
   @Override
   public DimFilter optimize()
   {
-    return Druids.newOrDimFilterBuilder().fields(Lists.transform(this.getFields(), new Function<DimFilter, DimFilter>()
-    {
-      @Override
-      public DimFilter apply(DimFilter input)
-      {
-        return input.optimize();
-      }
-    })).build();
+    List<DimFilter> elements = DimFilters.optimize(fields);
+    return elements.size() == 1 ? elements.get(0) : Druids.newOrDimFilterBuilder().fields(elements).build();
   }
 
   @Override
diff --git a/processing/src/test/java/io/druid/query/filter/SelectorDimFilterTest.java b/processing/src/test/java/io/druid/query/filter/SelectorDimFilterTest.java
index d146b1bc4d7..577297214dc 100644
--- a/processing/src/test/java/io/druid/query/filter/SelectorDimFilterTest.java
+++ b/processing/src/test/java/io/druid/query/filter/SelectorDimFilterTest.java
@@ -33,4 +33,20 @@ public class SelectorDimFilterTest
     SelectorDimFilter selectorDimFilter2 = new SelectorDimFilter("ab", "cd");
     Assert.assertFalse(Arrays.equals(selectorDimFilter.getCacheKey(), selectorDimFilter2.getCacheKey()));
   }
+
+  @Test
+  public void testSimpleOptimize()
+  {
+    SelectorDimFilter selectorDimFilter = new SelectorDimFilter("abc", "d");
+    DimFilter filter = new AndDimFilter(
+        Arrays.<DimFilter>asList(
+            new OrDimFilter(
+                Arrays.<DimFilter>asList(
+                    new AndDimFilter(Arrays.<DimFilter>asList(selectorDimFilter, null))
+                )
+            )
+        )
+    );
+    Assert.assertEquals(selectorDimFilter, filter.optimize());
+  }
 }