# 4. KGroupedStream / KGroupedTable Aggregation

![](/files/-MDTLVs-l0Oss2VUooLY)

In case of KTable we use Subtractor bcoz as we know here is the table it work for Upsert. (we are not considering previous record with same key) . KStream is just insert  , insert & insert only.

![](/files/-MDTMUjtd1tRPQwoD5lt)


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