Vasiliki Kalavri | Boston University 2020 map(String key, String value): // key: document name // value: document contents for each URL u in value: EmitIntermediate(u, "1"); reduce(String for distributed stream processing engines. ICDE 2015. • Nikos R. Katsipoulakis et. al. A holistic view of stream partitioning costs. VLDB 2017. • Rate-based optimization • Statis Viglas and Jeffrey

Make sure to read and become familiar with the format and schema document: • https://drive.google.com/file/d/0B5g07T_gRDg9Z0lsSTEtTWtpOW8/view Download and play around with “part-00000-of-00500.csv” of:

PyFlink jobs with Flink Kubernetes Operator. 1.1.2 QuickStart 1.1.2.1 QuickStart: Table API This document is a short introduction to the PyFlink Table API, which is used to help novice users quickly understand old_table = table_env.from_elements([(1, 'Hi'), (2, 'Hello')], ['id', 'data']) table_env.create_temporary_view('source_table', old_table) (continues on next page) 1.1. Getting Started 15 pyflink-docs, Release

PyFlink jobs with Flink Kubernetes Operator. 1.1.2 QuickStart 1.1.2.1 QuickStart: Table API This document is a short introduction to the PyFlink Table API, which is used to help novice users quickly understand old_table = table_env.from_elements([(1, 'Hi'), (2, 'Hello')], ['id', 'data']) table_env.create_temporary_view('source_table', old_table) (continues on next page) 1.1. Getting Started 15 pyflink-docs, Release

updates during downtimes, e.g. every night Streaming Data Warehouse • low-latency materialized view updates • pre-aggregated, pre-processed streams and historical data Data Management Approaches streams update materialized views. • An operator outputs event streams that describe the changing view computed over the input stream according to the relational semantics of the operator. 19 Vasiliki streams update materialized views. • An operator outputs event streams that describe the changing view computed over the input stream according to the relational semantics of the operator. src dest

disk 12 ??? Vasiliki Kalavri | Boston University 2020 13 • We express the computation from the view of a single vertex • Vertices communicate through messages • The computation proceeds in synchronous