diff --git a/store/iavlstore.go b/store/iavlstore.go
index 5f1917e2c2..a1a48722cb 100644
--- a/store/iavlstore.go
+++ b/store/iavlstore.go
@@ -126,8 +126,6 @@ func (st *iavlStore) Subspace(prefix []byte) Iterator {
 	i := 1
 
 	for !finished {
-		fmt.Printf("%v %v \n", len(end), i)
-		fmt.Printf("%v \n", end)
 		if end[len(end)-i] != byte(255) {
 			end[len(end)-i]++
 			finished = true
@@ -135,11 +133,12 @@ func (st *iavlStore) Subspace(prefix []byte) Iterator {
 			end[len(end)-i]++
 			i++
 			if i > len(end) {
-				end = []byte{}
+				end = nil
 				finished = true
 			}
 		}
 	}
+	fmt.Printf("%v \n", end)
 	return st.Iterator(prefix, end)
 }
 
@@ -243,6 +242,7 @@ func newIAVLIterator(tree *iavl.Tree, start, end []byte, ascending bool) *iavlIt
 		quitCh:    make(chan struct{}),
 		initCh:    make(chan struct{}),
 	}
+	fmt.Printf("%v   %v \n", iter.start, iter.end)
 	go iter.iterateRoutine()
 	go iter.initRoutine()
 	return iter
diff --git a/store/iavlstore_test.go b/store/iavlstore_test.go
index 85e02ba258..6e276c3d22 100644
--- a/store/iavlstore_test.go
+++ b/store/iavlstore_test.go
@@ -81,7 +81,7 @@ func TestIAVLIterator(t *testing.T) {
 		assert.EqualValues(t, value, treeData[expectedKey])
 		i += 1
 	}
-	assert.Equal(t, i, len(expected))
+	assert.Equal(t, len(expected), i)
 
 	iter = iavlStore.Iterator([]byte("golang"), []byte("rocks"))
 	expected = []string{"hello"}
@@ -92,7 +92,18 @@ func TestIAVLIterator(t *testing.T) {
 		assert.EqualValues(t, value, treeData[expectedKey])
 		i += 1
 	}
-	assert.Equal(t, i, len(expected))
+	assert.Equal(t, len(expected), i)
+
+	iter = iavlStore.Iterator([]byte("golang"), nil)
+	expected = []string{"hello"}
+	for i = 0; iter.Valid(); iter.Next() {
+		expectedKey := expected[i]
+		key, value := iter.Key(), iter.Value()
+		assert.EqualValues(t, key, expectedKey)
+		assert.EqualValues(t, value, treeData[expectedKey])
+		i += 1
+	}
+	assert.Equal(t, len(expected), i)
 }
 
 func TestIAVLSubspace(t *testing.T) {
@@ -117,7 +128,7 @@ func TestIAVLSubspace(t *testing.T) {
 		assert.EqualValues(t, value, expectedKey)
 		i += 1
 	}
-	assert.Equal(t, i, len(expected))
+	assert.Equal(t, len(expected), i)
 
 	iter = iavlStore.Subspace([]byte{byte(55), byte(255), byte(255)})
 	expected2 := [][]byte{
@@ -132,7 +143,7 @@ func TestIAVLSubspace(t *testing.T) {
 		assert.EqualValues(t, value, []byte("test4"))
 		i += 1
 	}
-	assert.Equal(t, i, len(expected))
+	assert.Equal(t, len(expected), i)
 
 	iter = iavlStore.Subspace([]byte{byte(255), byte(255)})
 	expected2 = [][]byte{
@@ -147,7 +158,7 @@ func TestIAVLSubspace(t *testing.T) {
 		assert.EqualValues(t, value, []byte("test4"))
 		i += 1
 	}
-	assert.Equal(t, i, len(expected))
+	assert.Equal(t, len(expected), i)
 }
 
 func TestIAVLStoreQuery(t *testing.T) {