1. Reporting and dashboarding This includes serving custom reporting for both internal and external developers for business insights and also many organizations using Presto for interactive A/B testing analytics. A defining characteristic of this use case is a requirement for low latency. It requires tens to hundreds of milliseconds at very high QPS, and not…
Overview Presto was originally designed to run interactive queries against data warehouses, but now it has evolved into a unified SQL engine on top of open data lake analytics for both interactive and batch workloads. Popular workloads on data lakes include: 1. Reporting and dashboarding This includes serving custom reporting for both internal and external…
Unnest is a common operation in Facebook’s daily Presto workload. It converts an ARRAY, MAP, or ROW into a flat relation. Its original implementation used deep copy all the time and was very inefficient. In Unnest Operator Performance Enhancement with Dictionary Blocks, the author improved the Unnest operator by up to 10x in CPU and…