Druid, what the diff? Using Apache Druid to report top changes in a metric between two intervals

At our company we are using Druid to power our time-based (as well as our non time-based) analytics dashboard. We looked into several options such as a relational database (Postgres) , Clickhouse and Elasticsearch. Taking into account the pros and cons of each,  we finally decided for Druid, as it was the leader in most query benchmarks. In fact,…