On MergeOnRead mode, when a record update more than once in a parttition, it does not work.

[kaka chen]

Hi All,
On MergeOnRead mode, when a record update more than once in a parttition,
it does not work.
I found It used HoodieAvroPayload, which is the default class of
"hoodie.compaction.payload.class", which preCombine method only return this.

@Override
public HoodieAvroPayload preCombine(HoodieAvroPayload another) {
return this;
}

So it will only return first update record on the log file.
As expected, it should return most recent update record.

Thanks,
Kaka Chen