# KStreams & KTables Advanced Operations (Stateful)

- [9. Summary Diagram ?](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/9.-summary-diagram.md)
- [8. What if I want to write to an external system?](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/8.-what-if-i-want-to-write-to-an-external-system.md)
- [7. KStream Transform / TransformValues](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/7.-kstream-transform-transformvalues.md)
- [6. KStream peek](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/6.-kstream-peek.md)
- [5. KGroupedStream /KGroupedTable Reduce](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/5.-kgroupedstream-kgroupedtable-reduce.md)
- [4. KGroupedStream / KGroupedTable Aggregation](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/4.-kgroupedstream-kgroupedtable-aggregation.md)
- [3. KGroupedStream / KGroupedTable Count](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/3.-kgroupedstream-kgroupedtable-count.md)
- [2. KTable groupBy](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/2.-ktable-groupby.md)
- [1. Section Objective](https://architectures.gitbook.io/project/apahce-kafka/kafka-streams-for-data-processing/kstreams-and-ktables-advanced-operations-stateful/1.-section-objective.md)


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