Problem: no command to fix corrupted data in versiondb

versiondb/tsrocksdb/store.go

@@ -100,8 +100,8 @@
 		prependStoreKey(storeKey, key),
 	)
 	if err != nil {
 		return nil, err
 	}
 	defer ts.Free()
 
 	if value.Exists() && s.skipVersionZero {
@@ -125,7 +125,7 @@
 // HasAtVersion implements VersionStore interface
 func (s Store) HasAtVersion(storeKey string, key []byte, version *int64) (bool, error) {
 	slice, err := s.GetAtVersionSlice(storeKey, key, version)
-	if err != nil {
+	if err != nil || slice == nil {
 		return false, err
 	}
 	defer slice.Free()
@@ -238,8 +238,8 @@
 func (s Store) FixData(storeNames []string) error {
 	for _, storeName := range storeNames {
 		if err := s.fixDataStore(storeName); err != nil {
 			return err
 		}
 	}
 
 	return nil
@@ -250,8 +250,8 @@
 	var version int64
 	iter, err := s.IteratorAtVersion(storeName, nil, nil, &version)
 	if err != nil {
 		return err
 	}
 	defer iter.Close()
 
 	batch := grocksdb.NewWriteBatch()
@@ -261,8 +261,8 @@
 	for ; iter.Valid(); iter.Next() {
 		key := iter.Key()
 		if len(key) < TimestampSize {
 			return fmt.Errorf("invalid key length: %X, store: %s", key, storeName)
 		}
 
 		ts := key[len(key)-TimestampSize:]
 		key = key[:len(key)-TimestampSize]
@@ -272,15 +272,15 @@
 		readOpts.SetTimestamp(ts)
 		oldValue, err := s.db.GetCF(readOpts, s.cfHandle, realKey)
 		if err != nil {
 			return err
 		}
 		readOpts.Destroy()
 
 		clean := bytes.Equal(oldValue.Data(), iter.Value())
 		oldValue.Free()
 
 		if clean {
 			continue
 		}
 
 		batch.PutCFWithTS(s.cfHandle, realKey, ts, iter.Value())