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Mohammed Galalen
Mohammed Galalen

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My Takeaways from "How Query Engines Work"

I was reading "How Query Engines Work" by Andy Grove and it was a fascinating deep dive into the internals of query engines. Here are my main takeaways:

  • SQL remains a popular interface for interacting with query engines and databases, facilitating efficient data retrieval.

  • SQL queries are translated into logical and physical plans, which are then optimized by the query engine's optimizer before execution.

  • Optimization rules like Projection Push-Down and Predicate Push-Down play a crucial role in enhancing performance.

  • To gain insights into query performance examine the query plan (In Postgres, you can use the command EXPLAIN SELECT * FROM mytable).

  • The optimized query plan is executed by the query engine's executor against the specified data source, resulting in the retrieval of the desired data.

  • Transaction Processing Council (TPC) Benchmarks are standardized tests used to evaluate the performance of database systems.

  • Datafusion: A fast and extensible query engine utilized in Apache Arrow, which is currently being used internally by InfluxDB.

  • The most interesting thing mentioned is Apache Flight Protocol built on top of gRPC, facilitates the seamless streaming of Arrow data over the network.

Link: https://howqueryengineswork.com/

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