Presto Parquet Column Encryption

By 

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….

Common Sub-Expression optimization

By 

The problem One common pattern we see in some analytical workloads is the repeated use of the same, often times expensive expression. Look at the following query plan for example: The expression JSON_PARSE(features) is used 6 times, and casted to different ROW structures for further processing. Traditionally, Presto would just execute the expression 6 times,…