What do you mean by "key" here? In my world a "key" is a half of a key-value-pair, and would correspond to only one record. But then you talk about strict ser

What do you mean by "key" here? In my world a "key" is a half of a key-value-pair, and would correspond to only one record. But then you talk about strict serializability of entire partitions and that seems like something different.