PT-05 What is a parallel seq scan in Postgresql ||

What Is a Parallel Sequential Scan? * A parallel sequential scan in PostgreSQL is a query execution strategy that divides the work of scanning a large table among multiple worker processes. Each worker scans a segment of the table, and the leader process (the main backend) gathers and merges the results. This approach leverages multi-core CPUs to speed up large data retrieval and processing tasks. When Should You Use a Parallel Sequential Scan? Large Tables: When you need to scan tables with millions or billions of rows. Non-Selective Queries: When most or all rows are returned, or when no suitable index exists. Analytical Workloads: For reporting, aggregation, or batch processing. Sufficient System Resources: When your system has enough CPU cores and memory to support parallel workers. Note: Parallel scans are less effective for small tables or queries that return only a few rows, as the overhead of coordinating workers can outweigh the benefits For more details you can refer this link https://medium.com/towardsdev/what-is-a-parallel-sequential-scan-in-postgresql-51bbd0c95b78