I've created a JIRA on this request. The idea here being some higher level descriptions of these projects (I included Calcite in the JIRA too), what they do for the project, what the current state of integration is, what options we have for future states, and what benefits those future states bring. For Parquet, I think we could go deeper into some of the settings/tweaks with real world examples to help folks do data better.
Thanks! https://issues.apache.org/jira/browse/DRILL-5471 On Tue, May 2, 2017 at 1:46 PM, Padma Penumarthy <[email protected]> wrote: > One thing I want to add is use_new_reader uses reader from parquet-mr > library, where as > default one is drill’s native reader which is supposed to be better, > performance wise. > But, it does not support complex types and we automatically switch to use > reader from parquet library > when we have to read complex types. > > Thanks, > Padma > > > On May 2, 2017, at 11:09 AM, Jinfeng Ni <[email protected]<mailto:jni@ > apache.org>> wrote: > > > - What the two readers are (is one a special drill thing, is the other a > standard reader from the parquet project?) > - What is the eventual goal here... to be able to use and switch between > both? To provide the option? To have code parity with another project? > > Both readers were for reading parquet data into Drill's value vector. > The default one (when store.parquet.use_new_reader is false) was > faster (based on measurements done by people worked on the two > readers), but it could not support complex type like map/array. The > new reader would be used by Drill either if you change the option to > true, or when the parquet data you are querying contain complex type > (even with the default option being false). Therefore, both readers > might be used by Drill code. > > There was a Parquet hackathon some time ago, which aimed to make > people in different projects using parquet work together to > standardize a vectorized reader. I did not keep track of that effort. > People with better knowledge of that may share their inputs. > > > - Do either of the readers work with Arrow? > > For now, neither works with Arrow, since Drill has not integrated with > Arrow yet. See DRILL-4455 for the latest discussion > (https://issues.apache.org/jira/browse/DRILL-4455). I would expect > Drill's parquet reader will work with Arrow, once the integration is > done. > >
