Presto Parquet Column Encryption

Introduction Apache Parquet modular encryption provides encryption at-rest and in-transit at finer-grained. In big data world, data analytic tables are usually very wide with hundreds of columns, while only a small number of columns need to be protected. So the finer-grained access control is a better fit than coarse-grained one like table level access control….

Faster Presto Queries with Parquet Page Index

Introduction Today’s data is growing very fast, which creates challenges for query engines like Presto. Presto is a popular interactive query engine, because of its scalability, high performance, and smooth integration with Hadoop. As the volume of data grows, Presto needs to read larger chunks of data and load them into memory, which causes higher…

Spatial Joins 1: Local Spatial Joins

A common type of spatial query involves relating one table of geometric objects (e.g., a table population_centers with columns population, latitude, longitude) with another such table (e.g., a table counties with columns county_name, boundary_wkt), such as calculating for each county the population sum of all population centers contained within it. These kinds of calculations are…