diff --git a/kv/cache_snapshot.go b/kv/cache_snapshot.go
index 9537c34727..63764800a6 100644
--- a/kv/cache_snapshot.go
+++ b/kv/cache_snapshot.go
@@ -74,9 +74,9 @@ func (c *cacheSnapshot) BatchGet(keys []Key) (map[string][]byte, error) {
 	return m, nil
 }
 
-// Scan scans values from snapshot and saves them in cache.
-func (c *cacheSnapshot) Scan(start, end Key, limit int) (map[string][]byte, error) {
-	values, err := c.snapshot.Scan(start, end, limit)
+// RangeGet gets values from snapshot and saves them in cache.
+func (c *cacheSnapshot) RangeGet(start, end Key, limit int) (map[string][]byte, error) {
+	values, err := c.snapshot.RangeGet(start, end, limit)
 	if err != nil {
 		return nil, errors.Trace(err)
 	}
diff --git a/kv/cache_snapshot_test.go b/kv/cache_snapshot_test.go
index 26c6efb7f2..044ee4a31b 100644
--- a/kv/cache_snapshot_test.go
+++ b/kv/cache_snapshot_test.go
@@ -14,8 +14,6 @@
 package kv
 
 import (
-	"bytes"
-
 	"github.com/juju/errors"
 	. "github.com/pingcap/check"
 )
@@ -53,17 +51,17 @@ func (s *testCacheSnapshotSuite) TestGet(c *C) {
 
 	v, err := s.cache.Get(s.k1)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v1), Equals, 0)
+	c.Assert(v, BytesEquals, s.v1)
 
 	s.store.Set(s.k1, s.v3)
 	v, err = s.cache.Get(s.k1)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v1), Equals, 0)
+	c.Assert(v, BytesEquals, s.v1)
 
 	s.store.Set(s.k2, s.v4)
 	v, err = s.cache.Get(s.k2)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v4), Equals, 0)
+	c.Assert(v, BytesEquals, s.v4)
 }
 
 func (s *testCacheSnapshotSuite) TestBatchGet(c *C) {
@@ -72,8 +70,8 @@ func (s *testCacheSnapshotSuite) TestBatchGet(c *C) {
 
 	m, err := s.cache.BatchGet([]Key{s.k1, s.k2, s.k3})
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(m[string(s.k1)], s.v1), Equals, 0)
-	c.Assert(bytes.Compare(m[string(s.k2)], s.v2), Equals, 0)
+	c.Assert(m[string(s.k1)], BytesEquals, s.v1)
+	c.Assert(m[string(s.k2)], BytesEquals, s.v2)
 	_, exist := m[string(s.k3)]
 	c.Assert(exist, IsFalse)
 
@@ -81,25 +79,25 @@ func (s *testCacheSnapshotSuite) TestBatchGet(c *C) {
 	s.store.Set(s.k1, s.v4)
 	v, err := s.cache.Get(s.k1)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v1), Equals, 0)
+	c.Assert(v, BytesEquals, s.v1)
 }
 
-func (s *testCacheSnapshotSuite) TestScan(c *C) {
+func (s *testCacheSnapshotSuite) TestRangeGet(c *C) {
 	s.store.Set(s.k1, s.v1)
 	s.store.Set(s.k2, s.v2)
 	s.store.Set(s.k3, s.v3)
 
-	m, err := s.cache.Scan(s.k1, s.k2, 100)
+	m, err := s.cache.RangeGet(s.k1, s.k2, 100)
 	c.Assert(err, IsNil)
 	c.Assert(len(m), Equals, 2)
-	c.Assert(bytes.Compare(m[string(s.k1)], s.v1), Equals, 0)
-	c.Assert(bytes.Compare(m[string(s.k2)], s.v2), Equals, 0)
+	c.Assert(m[string(s.k1)], BytesEquals, s.v1)
+	c.Assert(m[string(s.k2)], BytesEquals, s.v2)
 
 	// result should be saved in cache
 	s.store.Set(s.k1, s.v4)
 	v, err := s.cache.Get(s.k1)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v1), Equals, 0)
+	c.Assert(v, BytesEquals, s.v1)
 }
 
 type mockSnapshot struct {
@@ -125,7 +123,7 @@ func (s *mockSnapshot) BatchGet(keys []Key) (map[string][]byte, error) {
 	return m, nil
 }
 
-func (s *mockSnapshot) Scan(start, end Key, limit int) (map[string][]byte, error) {
+func (s *mockSnapshot) RangeGet(start, end Key, limit int) (map[string][]byte, error) {
 	m := make(map[string][]byte)
 	it := s.NewIterator([]byte(start))
 	defer it.Close()
diff --git a/kv/kv.go b/kv/kv.go
index da6054fe5c..02a03277f5 100644
--- a/kv/kv.go
+++ b/kv/kv.go
@@ -103,8 +103,9 @@ type Transaction interface {
 	Get(k Key) ([]byte, error)
 	// BatchGet gets a batch of values from KV store.
 	BatchGet(keys []Key) (map[string][]byte, error)
-	// Scan gets values in specific range from KV store.
-	Scan(start, end Key, limit int) (map[string][]byte, error)
+	// RangeGet gets values in the range [start, end] from KV store. Maximum
+	// number of values is up to limit.
+	RangeGet(start, end Key, limit int) (map[string][]byte, error)
 	// Set sets the value for key k as v into KV store.
 	Set(k Key, v []byte) error
 	// Seek searches for the entry with key k in KV store.
@@ -146,8 +147,9 @@ type Snapshot interface {
 	Get(k Key) ([]byte, error)
 	// BatchGet gets a batch of values from snapshot.
 	BatchGet(keys []Key) (map[string][]byte, error)
-	// Scan gets values in specific range from snapshot.
-	Scan(start, end Key, limit int) (map[string][]byte, error)
+	// RangeGet gets values in the range [start, end] from snapshot. Maximum
+	// number of values is up to limit.
+	RangeGet(start, end Key, limit int) (map[string][]byte, error)
 	// NewIterator gets a new iterator on the snapshot.
 	NewIterator(param interface{}) Iterator
 	// Release releases the snapshot to store.
@@ -185,7 +187,6 @@ type Storage interface {
 	Close() error
 	// Storage's unique ID
 	UUID() string
-
 	// CurrentVersion returns current max committed version.
 	CurrentVersion() (Version, error)
 }
diff --git a/kv/union_store_test.go b/kv/union_store_test.go
index 0eb4a2da24..94910520e0 100644
--- a/kv/union_store_test.go
+++ b/kv/union_store_test.go
@@ -13,11 +13,7 @@
 
 package kv
 
-import (
-	"bytes"
-
-	. "github.com/pingcap/check"
-)
+import . "github.com/pingcap/check"
 
 var _ = Suite(&testUnionStoreSuite{})
 
@@ -51,11 +47,11 @@ func (s *testUnionStoreSuite) TestGetSet(c *C) {
 	s.store.Set(s.k1, s.v1)
 	v, err := s.us.Get(s.k1)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v1), Equals, 0)
+	c.Assert(v, BytesEquals, s.v1)
 	s.us.Set(s.k1, s.v2)
 	v, err = s.us.Get(s.k1)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v2), Equals, 0)
+	c.Assert(v, BytesEquals, s.v2)
 }
 
 func (s *testUnionStoreSuite) TestDelete(c *C) {
@@ -68,7 +64,7 @@ func (s *testUnionStoreSuite) TestDelete(c *C) {
 	s.us.Set(s.k1, s.v2)
 	v, err := s.us.Get(s.k1)
 	c.Assert(err, IsNil)
-	c.Assert(bytes.Compare(v, s.v2), Equals, 0)
+	c.Assert(v, BytesEquals, s.v2)
 }
 
 func (s *testUnionStoreSuite) TestSeek(c *C) {
@@ -102,7 +98,7 @@ func checkIterator(c *C, iter Iterator, keys [][]byte, values [][]byte) {
 		v := values[i]
 		c.Assert(iter.Valid(), IsTrue)
 		c.Assert(iter.Key(), Equals, string(k))
-		c.Assert(bytes.Compare(iter.Value(), v), Equals, 0)
+		c.Assert(iter.Value(), BytesEquals, v)
 		c.Assert(iter.Next(), IsNil)
 	}
 	c.Assert(iter.Valid(), IsFalse)
diff --git a/store/hbase/snapshot.go b/store/hbase/snapshot.go
index a611e3ffc1..e5a840a484 100644
--- a/store/hbase/snapshot.go
+++ b/store/hbase/snapshot.go
@@ -75,9 +75,10 @@ func (s *hbaseSnapshot) Get(k kv.Key) ([]byte, error) {
 // BatchGet implements kv.Snapshot.BatchGet().
 func (s *hbaseSnapshot) BatchGet(keys []kv.Key) (map[string][]byte, error) {
 	gets := make([]*hbase.Get, len(keys))
+	bColFamily, bQualifier := []byte(ColFamily), []byte(Qualifier)
 	for i, key := range keys {
 		g := hbase.NewGet(key)
-		g.AddColumn([]byte(ColFamily), []byte(Qualifier))
+		g.AddColumn(bColFamily, bQualifier)
 		gets[i] = g
 	}
 	rows, err := s.txn.BatchGet(s.storeName, gets)
@@ -87,16 +88,16 @@ func (s *hbaseSnapshot) BatchGet(keys []kv.Key) (map[string][]byte, error) {
 
 	m := make(map[string][]byte)
 	for _, r := range rows {
-		k := r.Row
+		k := string(r.Row)
 		v := r.Columns[FmlAndQual].Value
-		m[string(k)] = v
-		s.cache[string(k)] = v
+		m[k] = v
+		s.cache[k] = v
 	}
 	return m, nil
 }
 
-// Scan implements kv.Snapshot.Scan().
-func (s *hbaseSnapshot) Scan(start, end kv.Key, limit int) (map[string][]byte, error) {
+// RangeGet implements kv.Snapshot.RangeGet().
+func (s *hbaseSnapshot) RangeGet(start, end kv.Key, limit int) (map[string][]byte, error) {
 	scanner := s.txn.GetScanner([]byte(s.storeName), start, end, limit)
 	defer scanner.Close()
 
diff --git a/store/hbase/txn.go b/store/hbase/txn.go
index d2593f2456..930982722d 100644
--- a/store/hbase/txn.go
+++ b/store/hbase/txn.go
@@ -111,8 +111,8 @@ func (txn *hbaseTxn) BatchGet(keys []kv.Key) (map[string][]byte, error) {
 	return txn.UnionStore.Snapshot.BatchGet(encodedKeys)
 }
 
-func (txn *hbaseTxn) Scan(start, end kv.Key, limit int) (map[string][]byte, error) {
-	return txn.UnionStore.Snapshot.Scan(kv.EncodeKey(start), kv.EncodeKey(end), limit)
+func (txn *hbaseTxn) RangeGet(start, end kv.Key, limit int) (map[string][]byte, error) {
+	return txn.UnionStore.Snapshot.RangeGet(kv.EncodeKey(start), kv.EncodeKey(end), limit)
 }
 
 // GetInt64 get int64 which created by Inc method.
diff --git a/store/localstore/snapshot.go b/store/localstore/snapshot.go
index 06a8864f20..fea4efb64f 100644
--- a/store/localstore/snapshot.go
+++ b/store/localstore/snapshot.go
@@ -120,7 +120,7 @@ func (s *dbSnapshot) BatchGet(keys []kv.Key) (map[string][]byte, error) {
 	return m, nil
 }
 
-func (s *dbSnapshot) Scan(start, end kv.Key, limit int) (map[string][]byte, error) {
+func (s *dbSnapshot) RangeGet(start, end kv.Key, limit int) (map[string][]byte, error) {
 	m := make(map[string][]byte)
 	it := s.NewIterator(start)
 	defer it.Close()
diff --git a/store/localstore/txn.go b/store/localstore/txn.go
index 6ffaf67866..57b549c37a 100644
--- a/store/localstore/txn.go
+++ b/store/localstore/txn.go
@@ -129,8 +129,8 @@ func (txn *dbTxn) BatchGet(keys []kv.Key) (map[string][]byte, error) {
 	return txn.UnionStore.Snapshot.BatchGet(encodedKeys)
 }
 
-func (txn *dbTxn) Scan(start, end kv.Key, limit int) (map[string][]byte, error) {
-	return txn.UnionStore.Snapshot.Scan(kv.EncodeKey(start), kv.EncodeKey(end), limit)
+func (txn *dbTxn) RangeGet(start, end kv.Key, limit int) (map[string][]byte, error) {
+	return txn.UnionStore.Snapshot.RangeGet(kv.EncodeKey(start), kv.EncodeKey(end), limit)
 }
 
 func (txn *dbTxn) Set(k kv.Key, data []byte) error {