db.go
func (db *DB) batchSet(entries []*Entry) error {
	req, err := db.sendToWriteCh(entries)
	if err != nil {
		return err
	}

	return req.Wait()
}
func (db *DB) batchSet(entries []*Entry) error {
	req, err := db.sendToWriteCh(entries)
	if err != nil {
		return err
	}

	return req.Wait()
}
// batchSet applies a list of badger.Entry. If a request level error occurs it
// will be returned.
//   Check(kv.BatchSet(entries))