Let us assume that I have two operations which I can write easily using both APIs in PyFlink (e.g. a sum of a column over a TumblingWindow). Are there any performance differences when I use the predefined Table-API commands vs manually implementing the count in Python as a ProcessWindowFunction?

I’m new to Flink and Kafka, and I’m trying to create a Kafka sink to send a string in JSON format to Kafka. To achieve this, I need to build a JsonRowSerializationSchema. Here’s what I’ve tried so far:

I use apache pyflink 1.18.1. The input data type from apache flink kafka source is like below,