diff --git a/rocksdb/backup.pxd b/rocksdb/backup.pxd
index 8ac14a6f58a4421d327134458265867e44c7e54a..7a815dd303f408160196b188e1486ed3d361e827 100644
--- a/rocksdb/backup.pxd
+++ b/rocksdb/backup.pxd
@@ -28,7 +28,6 @@ cdef extern from "utilities/backupable_db.h" namespace "rocksdb":
         void GetBackupInfo(vector[BackupInfo]*) nogil except+
         Status RestoreDBFromBackup(BackupID, string&, string&) nogil except+
         Status RestoreDBFromLatestBackup(string&, string&) nogil except+
-        void DeleteBackupsNewerThan(uint64_t) nogil except+
 
     cdef BackupEngine* NewBackupEngine "rocksdb::BackupEngine::NewBackupEngine"(
             Env*,
diff --git a/rocksdb/db.pxd b/rocksdb/db.pxd
index 15f57094db162fbd1016bbc322de2d432cd09df4..4f2ef016d2910092072050654bdd12a31b62d7e6 100644
--- a/rocksdb/db.pxd
+++ b/rocksdb/db.pxd
@@ -17,8 +17,8 @@ cdef extern from "rocksdb/write_batch.h" namespace "rocksdb":
         void Delete(const Slice&) nogil except+
         void PutLogData(const Slice&) nogil except+
         void Clear() nogil except+
-        string Data() nogil except+
-        int Count() nogil const
+        const string& Data() nogil except+
+        int Count() nogil except+
 
 cdef extern from "rocksdb/db.h" namespace "rocksdb":
     ctypedef uint64_t SequenceNumber