aljoscha commented on a change in pull request #14312: URL: https://github.com/apache/flink/pull/14312#discussion_r551366952
########## File path: docs/dev/datastream_execution_mode.md ########## @@ -237,6 +237,35 @@ next key. See [FLIP-140](https://cwiki.apache.org/confluence/x/kDh4CQ) for background information on this. +### Order of Processing + +The order in which records are processed in operators or user-defined functions (UDFs) can differ between `BATCH` and `STREAMING` execution. + +In `STREAMING` mode, user-defined functions should not make any assumptions about incoming records' order. +Data is processed as soon as it arrives. + +In `BATCH` execution mode, there are some operations where Flink guarantees order. +The ordering can be a side effect of the particular task scheduling, +network shuffle, and state backend (see above), or a conscious choice by the system. + +There are three general types of input that we can differentiate: + +- _broadcast input_: input from a broadcast stream (see also [Broadcast + State]({% link dev/stream/state/broadcast_state.md %})) +- _regular input_: input that isn't any of the above types of input Review comment: Ah damn, you're right... 🙈 fixing it ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
