diff --git a/store/boltdb/db.go b/store/boltdb/db.go
index 8212d08..f2cb1f3 100644
--- a/store/boltdb/db.go
+++ b/store/boltdb/db.go
@@ -152,6 +152,10 @@ func (db *DB) BatchPut(writes []driver.Write) error {
 	return err
 }
 
+func (db *DB) Compact() error {
+	return nil
+}
+
 func init() {
 	driver.Register(Store{})
 }
diff --git a/store/db.go b/store/db.go
index ca57326..99e6ed2 100644
--- a/store/db.go
+++ b/store/db.go
@@ -6,6 +6,11 @@ import (
 
 type DB struct {
 	driver.IDB
+	name string
+}
+
+func (db *DB) String() string {
+	return db.name
 }
 
 func (db *DB) NewIterator() *Iterator {
@@ -29,6 +34,10 @@ func (db *DB) NewSnapshot() (*Snapshot, error) {
 	return s, nil
 }
 
+func (db *DB) Compact() error {
+	return db.IDB.Compact()
+}
+
 func (db *DB) RangeIterator(min []byte, max []byte, rangeType uint8) *RangeLimitIterator {
 	return NewRangeLimitIterator(db.NewIterator(), &Range{min, max, rangeType}, &Limit{0, -1})
 }
diff --git a/store/driver/driver.go b/store/driver/driver.go
index 6da67df..859b840 100644
--- a/store/driver/driver.go
+++ b/store/driver/driver.go
@@ -23,6 +23,8 @@ type IDB interface {
 	NewSnapshot() (ISnapshot, error)
 
 	Begin() (Tx, error)
+
+	Compact() error
 }
 
 type ISnapshot interface {
diff --git a/store/goleveldb/db.go b/store/goleveldb/db.go
index e873feb..2a13f50 100644
--- a/store/goleveldb/db.go
+++ b/store/goleveldb/db.go
@@ -6,6 +6,7 @@ import (
 	"github.com/siddontang/goleveldb/leveldb/filter"
 	"github.com/siddontang/goleveldb/leveldb/opt"
 	"github.com/siddontang/goleveldb/leveldb/storage"
+	"github.com/siddontang/goleveldb/leveldb/util"
 
 	"github.com/siddontang/ledisdb/config"
 	"github.com/siddontang/ledisdb/store/driver"
@@ -180,6 +181,10 @@ func (db *DB) NewSnapshot() (driver.ISnapshot, error) {
 	return s, nil
 }
 
+func (db *DB) Compact() error {
+	return db.db.CompactRange(util.Range{nil, nil})
+}
+
 func init() {
 	driver.Register(Store{})
 	driver.Register(MemStore{})
diff --git a/store/hyperleveldb/db.go b/store/hyperleveldb/db.go
index 6d0e176..d6d7aeb 100644
--- a/store/hyperleveldb/db.go
+++ b/store/hyperleveldb/db.go
@@ -270,6 +270,11 @@ func (db *DB) Begin() (driver.Tx, error) {
 	return nil, driver.ErrTxSupport
 }
 
+func (db *DB) Compact() error {
+	C.leveldb_compact_range(db.db, nil, 0, nil, 0)
+	return nil
+}
+
 func init() {
 	driver.Register(Store{})
 }
diff --git a/store/leveldb/db.go b/store/leveldb/db.go
index 43ee0c2..92a2419 100644
--- a/store/leveldb/db.go
+++ b/store/leveldb/db.go
@@ -270,6 +270,11 @@ func (db *DB) Begin() (driver.Tx, error) {
 	return nil, driver.ErrTxSupport
 }
 
+func (db *DB) Compact() error {
+	C.leveldb_compact_range(db.db, nil, 0, nil, 0)
+	return nil
+}
+
 func init() {
 	driver.Register(Store{})
 }
diff --git a/store/mdb/mdb.go b/store/mdb/mdb.go
index d5c3987..ca79706 100644
--- a/store/mdb/mdb.go
+++ b/store/mdb/mdb.go
@@ -240,9 +240,6 @@ func (db MDB) Path() string {
 	return db.path
 }
 
-func (db MDB) Compact() {
-}
-
 func (db MDB) iterator(rdonly bool) *MDBIterator {
 	flags := uint(0)
 	if rdonly {
@@ -286,6 +283,10 @@ func (db MDB) NewSnapshot() (driver.ISnapshot, error) {
 	return newSnapshot(db)
 }
 
+func (db MDB) Compact() error {
+	return nil
+}
+
 func init() {
 	driver.Register(Store{})
 }
diff --git a/store/rocksdb/db.go b/store/rocksdb/db.go
index cc1ab81..1c79229 100644
--- a/store/rocksdb/db.go
+++ b/store/rocksdb/db.go
@@ -296,6 +296,11 @@ func (db *DB) Begin() (driver.Tx, error) {
 	return nil, driver.ErrTxSupport
 }
 
+func (db *DB) Compact() error {
+	C.rocksdb_compact_range(db.db, nil, 0, nil, 0)
+	return nil
+}
+
 func init() {
 	driver.Register(Store{})
 }
diff --git a/store/store.go b/store/store.go
index e2a6b85..d620c03 100644
--- a/store/store.go
+++ b/store/store.go
@@ -36,7 +36,7 @@ func Open(cfg *config.Config) (*DB, error) {
 		return nil, err
 	}
 
-	db := &DB{idb}
+	db := &DB{idb, s.String()}
 
 	return db, nil
 }
diff --git a/store/store_test.go b/store/store_test.go
index 5fdd95d..d2f2ca6 100644
--- a/store/store_test.go
+++ b/store/store_test.go
@@ -148,6 +148,9 @@ func checkIterator(it *RangeLimitIterator, cv ...int) error {
 	v := make([]string, 0, len(cv))
 	for ; it.Valid(); it.Next() {
 		k := it.Key()
+		if string(it.Value()) != "value" {
+			return fmt.Errorf("invalid value")
+		}
 		v = append(v, string(k))
 	}
 
@@ -175,7 +178,7 @@ func testIterator(db *DB, t *testing.T) {
 
 	for i := 0; i < 10; i++ {
 		key := []byte(fmt.Sprintf("key_%d", i))
-		value := []byte("")
+		value := []byte("value")
 		db.Put(key, value)
 	}