I don’t recall. Could you review the tests and see whether tests tend to use noDag=true or false most of the time? Are there any tests that use the less popular value, and if so, is there a particular reason that those tests use that option?
Julian > On Feb 12, 2019, at 6:47 AM, Stamatis Zampetakis <[email protected]> wrote: > > Hi all, > > I don't understand what is the correct way to set the noDag [1] parameter > in HepPlanner. I understand what it does (internal query graph becomes a > tree or a DAG) but I don't see why should I use the one or the other and > when. > > Is it performance related? > Are there implications on the rules that can be used with the planner? > Does it limit the class of queries that need to be transformed? > > Thanks in advance, > Stamatis > > [1] > https://github.com/apache/calcite/blob/883666929478aabe07ee5b9e572c43a6f1a703e2/core/src/main/java/org/apache/calcite/plan/hep/HepPlanner.java#L131
