Stream Processing Engine 2026。Apache Flink 2.0 (Stateful Stream Processing・Event Time+Watermark+Exactly-Once+Checkpoint+CEP)+Flink SQL+PyFlink+Flink CDC・Apache Spark 4.0 Structured Streaming (Micro-batch)+Spark SQL+Continuous Mode+Delta Live Tables・Apache Beam 2.x (Unified Batch+Stream Programming Model+Google Dataflow)・Apache Storm 2.x・Apache Kafka Streams (KStream+KTable)+ksqlDB・Materialize (Streaming SQL Materialized Views・Differential Dataflow Timely)・RisingWave (Apache 2.0 Streaming SQL・PostgreSQL互換・Rust)・Bytewax (Python Streaming・Rust core)・Samza+LinkedIn Apache Pulsar Functions・Pathway (Python+Rust Streaming)・GCP Dataflow+AWS Kinesis Data Analytics+Azure Stream Analytics・Confluent Cloud+Redpanda Cloud Streaming・Hazelcast Jet・Estuary Flow CDC・Watermarks+Tumbling/Hopping/Session Windows+Late Data+Backpressure・¥0 OSS-¥¥¥¥¥¥/Year、2026年Flink 2.0+Materialize+RisingWave+Spark Structured主流。