If the user changes the shuffle partition number between batches, Streaming aggregation will fail.
Here are some possible cases:
- Change "spark.sql.shuffle.partitions"
- Use "repartition" and change the partition number in codes
- RangePartitioner doesn't generate deterministic partitions. Right now it's safe as we disallow sort before aggregation. Not sure if we will add some operators using RangePartitioner in future.
Record # shuffle partitions in offset log and enforce in next batch