code: func DropDeltaIndexIDs(db *Lowlevel) {
  	dbi := db.NewIterator(util.BytesPrefix([]byte{KeyTypeIndexID}), nil)
  	defer dbi.Release()
  	for dbi.Next() {
  		db.Delete(dbi.Key(), nil)
  	}
  }
docs: // DropDeltaIndexIDs removes all delta index IDs from the database.
  // This will cause a full index transmission on the next connection.