Thank you very much, now I can see distribution in RelTrait, and I still have some doubts: 1. It seems in Calcite's main query process(via Prepare#prepareSql) there's no code to `addRelTraitDef(RelDistributionTraitDef.INSTANCE)`, and even no config, anyone know why? 2. I enable `useAbstractConvertersForConversion` and only register SMJ rule, the table has no collation when optimizing, it occurs error:
Missing conversions are EnumerableTableScan[sort: [] -> [0]] (2 cases) And when the table exposes collation, it just fine. How to make calcite automatically add sort nodes, like Spark's ensure requirements. Regards! Aron Tao Roman Kondakov <kondako...@mail.ru.invalid> 于2020年2月2日周日 下午7:26写道： Hi If you want the distribution trait to be taken into account by optimizer, you need to register it: VolcanoPlanner planner = ...; planner.addRelTraitDef(RelDistributionTraitDef.INSTANCE); See example in [1]. [1] https://github.com/apache/calcite/blob/a6f544eb48a87f4f71f76ed422584398c0c9baa3/core/src/test/java/org/apache/calcite/test/RelOptRulesTest.java#L6377 -- Kind Regards Roman Kondakov On 02.02.2020 08:01, JiaTao Tao wrote: > Hi > I wonder when will the exchange node be added to the execution plan. For > example, In Spark, if a join is SMJ(SortMergeJoin), it will add an > exchange and a sort node to the execution plan: > > 3631580619602_.pic.jpg > > In Calcite, Let me use CsvTest#testReadme for example and I can find a > sorting trait if the join is SMJ, but I can not find an exchange. > > The SQL: > > SELECT d.name <http://d.name>, COUNT(*) cnt > FROM emps AS e > JOIN depts AS d ON e.deptno = d.deptno > GROUP BY d.name <http://d.name>; > > The plan in volcano planner, see > `rel#76:EnumerableMergeJoin.ENUMERABLE.[[0], [2]]`, we can see the > conversion and the Collation, but no distribution. > > appendix > > Set#6, type: RecordType(INTEGER DEPTNO, VARCHAR NAME, INTEGER DEPTNO0) > rel#51:Subset#6.NONE.[], best=null, importance=0.6561 > > rel#49:LogicalJoin.NONE.[](left=RelSubset#30,right=RelSubset#29,condition==($2, > $0),joinType=inner), rowcount=1500.0, cumulative cost={inf} > > rel#60:LogicalProject.NONE.[](input=RelSubset#32,DEPTNO=$1,NAME=$2,DEPTNO0=$0), > rowcount=1500.0, cumulative cost={inf} > rel#55:Subset#6.ENUMERABLE.[], best=rel#78, > importance=0.7290000000000001 > > rel#70:EnumerableProject.ENUMERABLE.[](input=RelSubset#46,DEPTNO=$1,NAME=$2,DEPTNO0=$0), > rowcount=1500.0, cumulative cost={3686.517018598809 rows, 4626.25 cpu, > 0.0 io} > rel#76:EnumerableMergeJoin.ENUMERABLE.[[0], > [2]](left=RelSubset#74,right=RelSubset#75,condition==($2, > $0),joinType=inner), rowcount=1500.0, cumulative cost={inf} > > rel#78:EnumerableHashJoin.ENUMERABLE.[](left=RelSubset#30,right=RelSubset#69,condition==($0, > $2),joinType=inner), rowcount=1500.0, cumulative cost={2185.517018598809 > rows, 126.25 cpu, 0.0 io} > > -- > Regards! > > Aron Tao > > > -- > > Regards! > > Aron Tao >
