In this paper, we describe the Polaris distributed SQL query engine
https://www.vldb.org/pvldb/vol13/p3204-saborit.pdf
in Azure Synapse. It is the result of a multi-year project to rearchitect the query processing framework in the SQL DW parallel
data warehouse service, and addresses two main goals: (i) converge
data warehousing and big data workloads, and (ii) separate compute
and state for cloud-native execution.