This release includes extensions and fixes for the Druid adapter. New features were added, such as the capability to recognize and translate Timeseries and TopN Druid queries. Moreover, this release contains multiple bug fixes over the initial implementation of the adapter. It is worth mentioning that most of these fixes were contributed by Druid developers, which demonstrates the good reception of the adapter by that community.
We have added new SQL features too, e.g.,
There are multiple interesting extensions to the planner rules that should contribute to
obtain better plans, such as
avoiding doing the same join twice
in the presence of
COUNT DISTINCT, or being able to
simplify the expressions
in the plan further. In addition, we implemented a rule to
convert predicates on
EXTRACT function calls into date ranges.
The rule is not specific to Druid; however, in principle, it will be useful to identify
filter conditions on the time dimension of Druid data sources.
Finally, the release includes more than thirty bug-fixes, minor enhancements and internal changes to planner rules and APIs.