of a stream. • relation-to-stream: create streams through querying tables Declarative language: CQL 4 Vasiliki Kalavri | Boston University 2020 Select IStream(*) From S1 [Rows 5], S2 [Rows 10] Where of S2 stream-to-relation relation-to-relation relation-to-stream CQL Example 5 Vasiliki Kalavri | Boston University 2020 CQL relation-to-stream operators • Istream (for “insert stream”) applied 50], S2 [Rows 50] (A & B) || (C & D) Explicit conjunction and disjunction Implicit conjunction in CQL Consider events from stream S1 and stream S2 11 Vasiliki Kalavri | Boston University 2020 Operator

Relational Dataflow Input in-order out-of-order Results approximate exact Language SQL extensions, CQL Java, Scala, Python, SQL Execution centralized distributed Parallelism pipeline pipeline, task, data

-pyclientexec could be used. If it’s not specified, it will use the Python environment of the current shell. • Mix use of the above options You could also mix use of the above options, that is, pre-install client side in per-job mode. If it’s not specified, it will use the Python environment of the current shell environment. You could also execute PyFlink jobs in session mode as following: ./bin/flink run -t client side in per-job mode. If it’s not specified, it will use the Python environment of the current shell environment. 10 Chapter 1. How to build docs locally pyflink-docs, Release release-1.15 1.1.1.5

-pyclientexec could be used. If it’s not specified, it will use the Python environment of the current shell. • Mix use of the above options You could also mix use of the above options, that is, pre-install client side in per-job mode. If it’s not specified, it will use the Python environment of the current shell environment. You could also execute PyFlink jobs in session mode as following: ./bin/flink run -t client side in per-job mode. If it’s not specified, it will use the Python environment of the current shell environment. 10 Chapter 1. How to build docs locally pyflink-docs, Release release-1.16 1.1.1.5