In non-limiting examples of the present disclosure, systems, methods and devices for transmitting data stored in a source data store to a destination data store are presented. A plurality of data chunks may be received in a first format. At least one upsert operation may be performed on each of the data chunks for converting the first format to a format compatible with a destination data store schema. A transfer of the upserted data chunks to the destination data store may be executed. A determination may be made that at least one of the upserted data chunks has failed to transfer to the destination data store. Failed data chunks may be stored in a failed chunk retry data store. The at least one upsert operation may be re-performed on failed data chunks and a re-execution of the transfer of failed data chunks to the destination data store may be made.